Is Power

Description

Determine if the given number is a power of some non-negative integer.

Example

For n = 125, the output should be isPower(n) = true;
For n = 72, the output should be isPower(n) = false.

Input/Output

[execution time limit] 4 seconds (js)
[input] integer n

A positive integer.

Guaranteed constraints:
1 ≤ n ≤ 400.
[output] boolean
- true if n can be represented in the form a^b (a to the power of b) where a and b are some non-negative integers and b ≥ 2, false otherwise.

[JavaScript (ES6)] Syntax Tips

1
2
3
4
5
6
// Prints help message to the console
// Returns a string
function helloWorld(name) {
console.log("This prints to the console when you Run Tests");
return "Hello, " + name;
}

Solution

1
2
3
4
5
6
7
8
9
function isPower(n) {
  var i = 2;
  while (Math.pow(n, 1 / i) >= 2) {
    if (Math.ceil(Math.pow(Math.round(Math.pow(n, 1 / i)), i) == n))
      return true;
    i++;
  }
  return n === 1;
}