Question 245961 in Javascript Question posted in
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Javascript – How can i print how many times a number repeat inside an array? Js

I’m trying to solve this exercise:

Write a JavaScript code that asks the user for a number and then print the number of times that number appears in an array.

I’m doing it with parseFloat so I can get the string from the user with a <input /> and change it to number, then I declared my own array with numbers.

function repeatNumber() {
  const number = parseFloat(document.getElementById("number").value);
  const myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
  let compare = false;
  let count = 0;
  for (let i = 0; i < number.length; i++) {
    if (myArray[i] === number) {
      compare = true;
      count++;
    }
  }

  //compare is my id in a p tag where i'll show the result
  const repeating = document.getElementById("compare");

  repating.textContent = "Is your number in my array ?" + compare;
}
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src="/controlFlow/script.js"></script>
    <title>Js</title>
</head>
<body>
    <label for="number">Pls place a number to see if it's in my array</label>
    <input type="text" id="number">
    <button onclick="repeatNumber()">Check</button> 
    <p id="compare">  </p>
  
</body>
</html>
Tags:

3

Answers


  1. 0

    Maybe try this

    function repeatNumber() {

  const number = parseFloat(document.getElementById("number").value);
  const myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
  let compare = false;
  var count = 0;
  
  for (let i = 0; i < myArray.length; i++) {
    if (myArray[i] === number) {
      count++;
      compare = true;
    }
  }
  const repeating = document.getElementById("compare"); //compare is my id in a p tag where i'll show the result
  repating.textContent = "Is your number in my array ?" + compare;
  console.log(count);
}
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  2. 0

    It looks like there are a few issues in your code. You’re trying to loop through the number, but it should be an array, not a string. You also have a typo in repeating and a logical issue in the comparison. Here’s a corrected version of your code:

    <!DOCTYPE html>
<html>
<head>
  <title>Number Repeater</title>
</head>
<body>
  <input type="text" id="number" placeholder="Enter a number">
  <button onclick="repeatNumber()">Check</button>
  <p id="compare"></p>

  <script>
    function repeatNumber() {
      const inputNumber = parseFloat(document.getElementById("number").value);
      const myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
      let count = 0;

      for (let i = 0; i < myArray.length; i++) {
        if (myArray[i] === inputNumber) {
          count++;
        }
      }

      const repeating = document.getElementById("compare");
      repeating.textContent = "Your number appears " + count + " times in the array.";
    }
  </script>
</body>
</html>

    In this corrected code:

    1. We fixed the loop to iterate through the myArray and compared each element with the inputNumber.
    2. We used a count variable to keep track of how many times the number appears in the array.
    3. We updated the repeating element’s text content to display the count.
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  3. 0 
    function repeatNumber() {
        const numbers = [2, 4, 6, 4, 8, 4, 10, 4];
            const userInput = document.getElementById("number").value;
            const numberToCount = parseInt(userInput);
            if (!isNaN(numberToCount)) {
                const count = numbers.reduce((accumulator, currentValue) => {
                    return currentValue === numberToCount ? accumulator + 1 : accumulator;
                }, 0);

                const resultElement = document.getElementById("compare");
                resultElement.textContent = `Is your number in my array ? ${count} `;
            } else {
                alert("Invalid input. Please enter a valid number.");
            }
        }
    <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src="/controlFlow/script.js"></script>
    <title>Js</title>
</head>
<body>
    <label for="number">Pls place a number to see if it's in my array</label>
    <input type="text" id="number">
    <button onclick="repeatNumber()">Check</button> 
    <p id="compare">  </p>
  
</body>
</html>
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