JavaScript: Find the first not repeated character

Last update on May 30 2022 10:05:47 (UTC/GMT +8 hours)

JavaScript Function: Exercise-23 with Solution

Write a JavaScript function to find the first not repeated character.

Sample arguments : 'abacddbec'
Expected output : 'e'

Pictorial Presentation:

JavaScript: Find the first not repeated character

Sample Solution: -

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>find the first not repeated character.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function find_FirstNotRepeatedChar(str) {
  var arra1 = str.split('');
  var result = '';
  var ctr = 0;
 
  for (var x = 0; x < arra1.length; x++) {
    ctr = 0;
 
    for (var y = 0; y < arra1.length; y++) 
    {
      if (arra1[x] === arra1[y]) {
        ctr+= 1;
      }
    }
 
    if (ctr < 2) {
      result = arra1[x];
      break;
    }
  }
  return result;
}
console.log(find_FirstNotRepeatedChar('abacddbec'));

Sample Output:

Flowchart:

Live Demo:

See the Pen JavaScript - Find the first not repeated character-function-ex- 23 by w3resource (@w3resource) on CodePen.

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Previous: Write a JavaScript function that accepts two arguments, a string and a letter and the function will count the number of occurrences of the specified letter within the string.
Next: Write a JavaScript function to apply Bubble Sort algorithm.

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JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = [];
arr[0] = "Jani";
arr[1] = "Hege";
arr[2] = "Stale";
arr[3] = "Kai Jim";
arr[4] = "Borge";

console.log(arr.join());
arr.splice(2, 0, "Lene");
console.log(arr.join());

Ref: https://bit.ly/2BXbp04