JavaScript: Find the maximum integer n

Last update on May 30 2022 10:01:23 (UTC/GMT +8 hours)

JavaScript Basic: Exercise-145 with Solution

Write a JavaScript program to find the maximum integer n such that 1 + 2 + ... + n <= a given integer.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Find the maximum integer n.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function sumn(val) {
  var sn = 0;
  var i = 0;
  while (sn <= val) {
    sn += i++;
  }
  return i - 2;
}
console.log(sumn(11))
console.log(sumn(15))

Sample Output:

4
5

Flowchart:

ES6 Version:

function sumn(val) {
  let sn = 0;
  let i = 0;
  while (sn <= val) {
    sn += i++;
  }
  return i - 2;
}
console.log(sumn(11))
console.log(sumn(15))

Live Demo:

See the Pen javascript-basic-exercise-145 by w3resource (@w3resource) on CodePen.

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Next: Write a JavaScript program to compute the sum of cubes of all integer from 1 to a given integer.

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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