So my code currently only puts -boink or -bork after the entire string once the conditions are met but I want it so that after every single word the terms get added based on whether or not it satisfies the conditions of being either greater or less than five characters.
For example "My-boink name-boinkk is-boink Emmanuel-bork"
function myFunctionOne(input1, input2) {
var prompt1 = prompt("Please enter 1, 2, 3, or Exit").toLowerCase();
var prompt2 = input2;
if (prompt1 == 1) {
prompt2 = prompt("Please enter a string");
while (prompt2.length === 0) {
prompt2 = prompt("You need to enter something");
}
myFunctionOne(prompt1, prompt2);
}
if (prompt1 == 2) {
if (prompt2.length > 5) {
console.log(prompt2 + "-bork");
}
myFunctionOne(prompt2);
}
else {
console.log(prompt2 + "-boink")
}
}
myFunctionOne(1, 2, null);
You need to split the string into words with the split method and then loop through them using a for loop to check if they're longer than 5 characters and add 'bork' or 'boink' and then join the words again.
I could write the code for you, but I think it will be more satisfying for you to do it yourself. If you want me to write it thought let me know.
Edit
I'm going to write the code as close as what you already have as posible
function myFunctionOne(input1, input2) {
var prompt1 = prompt("Please enter 1, 2, 3, or Exit").toLowerCase();
var prompt2 = input2;
if (prompt1 == 1) {
prompt2 = prompt("Please enter a string");
while (prompt2.length === 0) {
prompt2 = prompt("You need to enter something");
}
myFunctionOne(prompt1, prompt2);
}
if (prompt1 == 2) {
var words = prompt2.split(" "); // we separate the string into words dividing them by space into an array called words
for(var i = 0; i < words.length; i++){ // we loop from 0 to the length of the array - 1 to access all positions in the array (the last position in arrays are always the length of the array - 1 because they start at 0)
if(words[i].length > 5){ //we check if the word in this position of the array is longer than 5 characters
words[i] += "-bork"; //if it is we add -bork
}else{
words[i] += "-boink" //if it is not longer than 5 characters we add -boink
}
}
console.log(words.join(" ")); //we print the array joining the elements with an space to form a string
}
}
myFunctionOne(1, 2, null);
I'm a little confused by what's going on at the top of your code, so I'm not going to refactor the entire thing. I'm going to provide an explanation from the time we have our string.
One approach would be to use .split(), which will return an array of string values based on what character you choose to split the string by. The reason we need to do this is because your code is currently looping through each string, rather than each word in the string. In this instance, I'm assuming your string can't take punctuation like commas or periods. If that's the case, you want to split by empty spaces, so it would look like string.split(" ").
Then, you could use the map() array method to loop through every value in the array and perform a function on it. Note, the map() method will return a new array, so best to save this into a new variable.
Then, you could use the .join() method, which will join the values of an array based on some value (essentially the opposite of .split()). Again, assuming no punctuation, I'd join the array with a space so that the values have a space between them, which would look like array.join(" ").
I've included some mock code below.
const string = prompt("Please enter your string");
const stringToArray = string.split(" ");
console.log(stringToArray);
const filteredArray = stringToArray.map((string) => {
if (string.length > 5) {
return string + "-bork";
}
return string + "-boink";
});
console.log(filteredArray);
const joinedFilteredArray = filteredArray.join(" ");
console.log(joinedFilteredArray);
Related
You are given a string with words and numbers separated by whitespaces (one space). The words contains only letters. You should check if the string contains three words in succession. For example, the string "start 5 one two three 7 end" contains three words in succession.
Input : String
Output : Boolean
This is what I'm trying to do, please point out my mistake. Thanks.
function threeWords(text){
let lst = text.split(' ');
for (let i=0; i< 3; i++) {
if (typeof lst[i] === 'string' && Number(lst[i]) === NaN) {return true}
else {return false;}}
}
If you'd rather continue with your code than use regex, here are your issues:
You only loop over 3 of the elements in lst. Loop over the entire length of the list.
You try to check if Number('somestring') === NaN. In JavaScript, NaN === NaN is False. Use isNaN() instead.
Once you find a list element that is not a number, you return True. You should have a variable that keeps track of how many words there are in succession (resetting to 0 when you find a number), and return True when this variable is equal to 3.
Here is the fixed code:
function threeWords(text) {
let lst = text.split(' ');
let num_words = 0;
for (let i = 0; i < lst.length; i++) {
if (isNaN(Number(lst[i])))
num_words++
else
num_words = 0
if (num_words === 3)
return true
}
return false;
}
Might be easier with a regular expression:
const result = /([A-Za-z]+( |$)){3}/.test('start 5 one two three 7 end');
console.log(result);
In JavaScript, I need validate phone numbers without using regular expressions (must be with string manipulation). The phone numbers have to be in one of the following formats:
123-456-7890
1234567890
(123)4567890
(123)456-7890
Then I must also provide an alert if the phone number isn't in one of the formats listed above.
I have only been able to manage to get #2 working, which looks something like this:
function len(gth)
{
if (gth.value.length != 10)
{
alert("Telephone numbers MUST be 10 digits!");
}
}
which down in the HTML it would call up to the function:
<p>Phone: <input id = "phone" onblur="len(this)" name = "Phone" size = "20" type = "text" maxlength = "10"> </p>
Since you need a solution without regex, I believe this should work.
const phones = [
'123-456-7890',
'1234567890',
'(123)4567890',
'(123)456-7890',
'+61(123) 456-7890',
'12345',
'))))01/34$89.77(99'
]
function len(gth) {
if (gth.substring(3, 4) == '-' && gth.substring(7, 8) == '-') // 123-456-7890
gth = gth.replace('-', '').replace('-', '');
else if (gth.substring(0, 1) == '(' && gth.substring(4, 5) == ')' && gth.substring(8, 9) == '-') // (123)456-7890
gth = gth.replace('(', '').replace(')', '').replace('-', '');
else if (gth.substring(0, 1) == '(' && gth.substring(4, 5) == ')') // (123)4567890
gth = gth.replace('(', '').replace(')', '');
if (!isNaN(gth) && gth.length == 10) {
return true;
}
alert("Telephone numbers:" + gth + " MUST be 10 digits!");
}
phones.forEach(len)
I would replace the numbers with something like x, then check against predefined patterns:
function check(num) {
let pattern = '';
for (let i = 0; i < num.length; i++) {
pattern += num[i] >= '0' && num[i] <= '9' ? 'x' : num[i];
}
return ['xxx-xxx-xxxx', 'xxxxxxxxxx', '(xxx)xxxxxxx', '(xxx)xxx-xxxx']
.indexOf(pattern) >= 0;
}
For extra credit, find the bug in the above program.
However, you don't really need to do any of this. You should be able to use the pattern attribute on the input element. That will also provide a better user experience. For instance, you can style the input element using the :invalid pseudo-class, by putting a red border around it for example, to give the user real-time feedback that their input is not valid. Yes, that takes a regular expression--what was your reason for not wanting to use a regular expression again?
You can make it manually be:
Checking string size if it is the expected or not
split the string to char array then parse them as integers inside a try block if numberFormatException is thrown it should be a bracket ( ) or -
Basic example of extracting the input data to Array
function test() {
var phnTest = document.getElementById('phone').value;
var strArray = [];
strArray = phnTest.split('');
document.getElementById('p').innerHTML = strArray;
}
<form action="demo_form.asp">
Phone <input id="phone" type="text" name="phone"><br>
<input type="button" value='Submit' onclick="test()">
</form>
<p id='p'></p>
This is dependent on how the data is structured, if you need to search a body of text and so on, but basics would be...
If it's a simple pull from an <input>, grab the data...
Take the input data, and generate an array with each character. You could then test, say strArray[3], for a dash or a dot. If not present, it can continue along to check for seven numbers in a row and so on.
This is going to be extremely consuming and require a number of conditionals to be checked. I assume the "without RegEx" is a requirement for a project or such, if not, recommend learning and using RegEx.
Hope this gets you going.
This is my attempt. The key is creating an array from the string then filtering out any non numerical characters. It would be easier to use regular expression though. just
number.replace(/(\D+)/g, '')
const numbers = [
'123-456-7890',
'1234567890',
'(123)4567890',
'(123)456-7890',
'+61(123) 456-7890',
'12345',
'))))01/34$89.77(99'
]
// validate a phone number
function validate(number) {
const digits = clean(number)
console.log({
number,
digits,
length: digits.length,
pass: digits.length === 10
})
}
// remove any non digits from the number
function clean(number) {
return Array.from(number).filter(char => {
return !isNaN(char) && char !== ' '
}).join('')
}
numbers.forEach(validate)
I've been on this problem for several hours now and have done all I can to the best of my current newbie javaScript ability to solve this challenge but I just can't figure out exactly what's wrong. I keep getting "UNEXPECTED TOKEN ILLEGAL on here: http://jsfiddle.net/6n8apjze/14/
and "TypeError: Cannot read property 'length' of null": http://goo.gl/LIz89F
I think the problem is the howManyRepeat variable. I don't understand why I'm getting it can't read the length of null when clearly word is a word from str...
I got the idea for:
word.toLowerCase().split("").sort().join("").match(/([.])\1+/g).length
...here: Get duplicate characters count in a string
The Challenge:
Using the JavaScript language, have the function LetterCountI(str) take the str
parameter being passed and return the first word with the greatest number of
repeated letters. For example: "Today, is the greatest day ever!" should return
greatest because it has 2 e's (and 2 t's) and it comes before ever which also
has 2 e's. If there are no words with repeating letters return -1. Words will
be separated by spaces.
function LetterCountI(str){
var wordsAndAmount={};
var mostRepeatLetters="-1";
var words=str.split(" ");
words.forEach(function(word){
// returns value of how many repeated letters in word.
var howManyRepeat=word.toLowerCase().split("").sort().join("").match(/([.])\1+/g).length;
// if there are repeats(at least one value).
if(howManyRepeat !== null || howManyRepeat !== 0){
wordsAndAmount[word] = howManyRepeat;
}else{
// if no words have repeats will return -1 after for in loop.
wordsAndAmount[word] = -1;
}
});
// word is the key, wordsAndAmount[word] is the value of word.
for(var word in wordsAndAmount){
// if two words have same # of repeats pick the one before it.
if(wordsAndAmount[word]===mostRepeatLetters){
mostRepeatLetters=mostRepeatLetters;
}else if(wordsAndAmount[word]<mostRepeatLetters){
mostRepeatLetters=mostRepeatLetters;
}else if(wordsAndAmount[word]>mostRepeatLetters){
mostRepeatLetters=word;
}
}
return mostRepeatLetters;
}
// TESTS
console.log("-----");
console.log(LetterCountI("Today, is the greatest day ever!"));
console.log(LetterCountI("Hello apple pie"));
console.log(LetterCountI("No words"));
Any guidance is much appreciated. Thank you!! ^____^
Here is the working code snippet:
/*
Using the JavaScript language, have the function LetterCountI(str) take the str
parameter being passed and return the first word with the greatest number of
repeated letters. For example: "Today, is the greatest day ever!" should return
greatest because it has 2 e's (and 2 t's) and it comes before ever which also
has 2 e's. If there are no words with repeating letters return -1. Words will
be separated by spaces.
console.log(LetterCountI("Today, is the greatest day ever!") === "greatest");
console.log(LetterCountI("Hello apple pie") === "Hello");
console.log(LetterCountI("No words") === -1);
Tips:
This is an interesting problem. What we can do is turn the string to lower case using String.toLowerCase, and then split on "", so we get an array of characters.
We will then sort it with Array.sort. After it has been sorted, we will join it using Array.join. We can then make use of the regex /(.)\1+/g which essentially means match a letter and subsequent letters if it's the same.
When we use String.match with the stated regex, we will get an Array, whose length is the answer. Also used some try...catch to return 0 in case match returns null and results in TypeError.
/(.)\1+/g with the match method will return a value of letters that appear one after the other. Without sort(), this wouldn't work.
*/
function LetterCountI(str){
var wordsAndAmount={};
var mostRepeatLetters="";
var words=str.split(" ");
words.forEach(function(word){
var howManyRepeat=word.toLowerCase().split("").sort().join("").match(/(.)\1+/g);
if(howManyRepeat !== null && howManyRepeat !== 0){ // if there are repeats(at least one value)..
wordsAndAmount[word] = howManyRepeat;
} else{
wordsAndAmount[word] = -1; // if no words have repeats will return -1 after for in loop.
}
});
// console.log(wordsAndAmount);
for(var word in wordsAndAmount){ // word is the key, wordsAndAmount[word] is the value of word.
// console.log("Key = " + word);
// console.log("val = " + wordsAndAmount[word]);
if(wordsAndAmount[word].length>mostRepeatLetters.length){ //if two words have same # of repeats pick the one before it.
mostRepeatLetters=word;
}
}
return mostRepeatLetters ? mostRepeatLetters : -1;
}
// TESTS
console.log("-----");
console.log(LetterCountI("Today, is the greatest day ever!"));
console.log(LetterCountI("Hello apple pie"));
console.log(LetterCountI("No words"));
/*
split into words
var wordsAndAmount={};
var mostRepeatLetters=0;
loop through words
Check if words has repeated letters, if so
Push amount into object
Like wordsAndAmount[word[i]]= a number
If no repeated letters...no else.
Loop through objects
Compare new words amount of repeated letters with mostRepeatLetters replacing whoever has more.
In the end return the result of the word having most repeated letters
If all words have no repeated letters return -1, ie.
*/
The changes made:
[.] turned into . as [.] matches a literal period symbol, not any character but a newline
added closing */ at the end of the code (the last comment block was not closed resulting in UNEXPECTED TOKEN ILLEGAL)
if(howManyRepeat !== null || howManyRepeat !== 0) should be replaced with if(howManyRepeat !== null && howManyRepeat !== 0) since otherwise the null was testing for equality with 0 and led to the TypeError: Cannot read property 'length' of null" issue. Note that .match(/(.)\1+/g).length cannot be used since the result of matching can be null, and this will also cause the TypeError to appear.
The algorithm for getting the first entry with the greatest number of repetitions was wrong since the first if block allowed subsequent entry to be output as a correct result (not the first, but the last entry with the same repetitions was output actually)
-1 can be returned if mostRepeatLetters is empty.
Hope you dont mind if I rewrite this code. My code may not be that efficient.
Here is a snippet
function findGreatest() {
// ipField is input field
var getString = document.getElementById('ipField').value.toLowerCase();
var finalArray = [];
var strArray = [];
var tempArray = [];
strArray = (getString.split(" "));
// Take only those words which has repeated letter
for (var i = 0, j = strArray.length; i < j; i++) {
if ((/([a-zA-Z]).*?\1/).test(strArray[i])) {
tempArray.push(strArray[i]);
}
}
if (tempArray.length == 0) { // If no word with repeated Character
console.log('No such Word');
return -1;
} else { // If array has words with repeated character
for (var x = 0, y = tempArray.length; x < y; x++) {
var m = findRepWord(tempArray[x]); // Find number of repeated character in it
finalArray.push({
name: tempArray[x],
repeat: m
})
}
// Sort this array to get word with largest repeated chars
finalArray.sort(function(z, a) {
return a.repeat - z.repeat
})
document.getElementById('repWord').textContent=finalArray[0].name;
}
}
// Function to find the word which as highest repeated character(s)
function findRepWord(str) {
try {
return str.match(/(.)\1+/g).length;
} catch (e) {
return 0;
} // if TypeError
}
Here is DEMO
function LetterCountI(str) {
var word_arr = str.split(" ");
var x = word_arr.slice();
for(var i = 0; i < x.length; i ++){
var sum = 0;
for(var y = 0; y < x[i].length; y++){
var amount = x[i].split("").filter(function(a){return a == x[i][y]}).length;
if (amount > 1){
sum += amount
}
}
x[i] = sum;
}
var max = Math.max.apply(Math,x);
if(max == 0)
return -1;
var index = x.indexOf(max);
return(word_arr[index]);
};
Here is another version as well.
You could use new Set in the following manner:
const letterCount = s => {
const res = s.split(' ')
.map(s => [s, (s.length - new Set([...s]).size)])
.reduce((p, c) => (!p.length) ? c
: (c[1] > p[1]) ? c : p, []);
return !res[1] ? -1 : res.slice(0,1).toString()
}
Note: I have not tested this solution (other than the phrases presented here), but the idea is to subtract unique characters from the total characters in each word of the phrase.
My code isn't working, can someone please tell me what the problem is?
I'm guessing it's the for loop, but I cannot find the problem.
<html>
<body>
<script>
username = prompt("Please enter a your username:");
for (var i = 0; i < username; i++) {
if(isFinite(username.charAt(i))) {
result = true;
document.write("The username consists of one or more numbers." + BR);
}
else {
result = false;
document.write("The username must consist of one or more numbers." + BR);
}
}
</script>
</body>
</html>
You have two problems in your code:
In the for loop, use the length of the variable to establish the stop condition
for (var i = 0; i < username.length; i++)
BR is not defined
Working code: http://jsfiddle.net/f643fr4w/
From the output I can probably assume you just want to check if username consists of at least one number, actually: a digit.
// iterate over the input
for (var i = 0; i < username.length; i++) {
// check if it is a number (not a digit but that's the same here)
if (isFinite(username.charAt(i))) {
result = true;
// The requirement "one or more numbers" is fulfilled,
// we can break out of the loop
break;
}
else {
result = false;
}
// print something according to "result"
if(result === true){
document.write('The username consists of one or more numbers.');
} else {
document.write('The username must consist of one or more numbers.');
}
}
You have to go over the full length of the string to find out if there's no number but not if you want to find out if there is any number in it.
Now, if you want to test if it consists of only digits you have to reword the requirements, they are a bit too ambiguous now.
Additional hints:
you need to check the input, you always have to check user input!
you need to be aware that JavaScript strings are UTF16. Rarely a problem but gets easily one if you iterate over JavaScript strings.
String.charAt() returns a character, not a number. Don't rely on the automatic conversions in JavaScript, you way too easily shoot yourself in the foot if you rely on it but also if you don't, so be careful.
please don't use document.write, use either the console if available or change the text-node of an HTML element.
With these points in mind you may get something like this:
// make a list of digits
var digits = ['0','1','2','3','4','5','6','7','8','9'];
// ask the user for a username
var username = prompt("Please enter a your username:");
// check input
if (username.length === 0) {
console.log('no username given');
} else {
for (var i = 0; i < username.length; i++) {
// indexOf searches for the same type, that's why the digits above
// are strings with quotes around them
if (digits.indexOf(username.charAt(i)) >= 0) {
result = true;
// The requirement "one or more numbers" is fullfilled,
// we can break out of the loop
break;
}
else {
result = false;
}
}
// print something according to "result"
if (result === true) {
console.log('The username consists of one or more numbers.');
} else {
console.log('The username must consist of one or more numbers.');
}
}
The above is one variation of many and could easily give rise to a heated discussion on some forums (not here! Of course not! ;-) ) but I hope it helps.
Use a regex for such shenanigans:
var username = prompt("username plz kk thx");
var result = /[0-9]/.test(username);
document.write("The username " + (result ? "consists" : "must consist") + " of one or more numbers");
My whole goal was to write a loop that would take a string, count the letters and return two responses: one = "this word is symmetric" or two = "this word is not symmetric". However the code I wrote doesn't console anything out. Here's the code:
var arya = function(arraycount){
for (arraycount.length >= 1; arraycount.length <= 100; arraycount++) {
while (arraycount.length%2 === 0) {
console.log("This is a symmetric word and its length is " + " " arraycount.length " units.");
arraycount.length%2 != 0
console.log("Not a symmetric word");
}
}
}
arya("Michael");
There are many ways to accomplish your goal, but here are a few. The first is a somewhat naïve approach using a for loop, and the second uses recursion. The third asks whether the string equals the reverse of the string.
iterative (for loop) function
var isPalindromeIteratively = function(string) {
if (string.length <= 1) {
return true;
}
for (var i = 0; i <= Math.floor(string.length / 2); i++) {
if (string[i] !== string[string.length - 1 - i]) {
return false;
}
}
return true;
};
This function begins by asking whether your input string is a single character or empty string, in which case the string would be a trivial palindrome. Then, the for loop is set up: starting from 0 (the first character of the string) and going to the middle character, the loop asks whether a given character is identical to its partner on the other end of the string. If the parter character is not identical, the function returns false. If the for loop finishes, that means every character has an identical partner, so the function returns true.
recursive function
var isPalindromeRecursively = function(string) {
if (string.length <= 1) {
console.log('<= 1');
return true;
}
var firstChar = string[0];
var lastChar = string[string.length - 1];
var substring = string.substring(1, string.length - 1);
console.log('first character: ' + firstChar);
console.log('last character: ' + lastChar);
console.log('substring: ' + substring);
return (firstChar === lastChar) ? isPalindromeRecursively(substring) : false;
};
This function begins the same way as the first, by getting the trivial case out of the way. Then, it tests whether the first character of the string is equal to the last character. Using the ternary operator, the function, returns false if that test fails. If the test is true, the function calls itself again on a substring, and everything starts all over again. This substring is the original string without the first and last characters.
'reflecting' the string
var reflectivePalindrome = function(string) {
return string === string.split('').reverse().join('');
};
This one just reverses the string and sees if it equals the input string. It relies on the reverse() method of Array, and although it's the most expressive and compact way of doing it, it's probably not the most efficient.
usage
These will return true or false, telling you whether string is a palindrome. I assumed that is what you mean when you say "symmetric." I included some debugging statements so you can trace this recursive function as it works.
The Mozilla Developer Network offers a comprehensive guide of the JavaScript language. Also, here are links to the way for loops and while loops work in JS.