Problem:
Score : 200 points

Problem Statement

Find the largest square number not exceeding N. Here, a square number is an integer that can be represented as the square of an integer.

Constraints

1 \leq N \leq 10^9

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the largest square number not exceeding N.

Sample Input 1

10

Sample Output 1

9

10 is not square, but 9 = 3 × 3 is. Thus, we print 9.

Sample Input 2

81

Sample Output 2

81

Sample Input 3

271828182

Sample Output 3

271821169

Solution in JavaScript (node.js v5.12) (judge verdict: Runtime Error)

function Main(input)
{
  input = input.split("\n");

  var a = parseInt(input[0], 10);
  for(let i = 1; i <= a; i++)
  {
    if (Math.pow(a, 0.5) % 1 != 0) {
      a -= 1;
    }else{
      console.log(a);
      break;
    }
  }



  // console.log('%d', a);
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));