LeetCode-in-Java

633. Sum of Square Numbers

Medium

Given a non-negative integer c, decide whether there’re two integers a and b such that a2 + b2 = c.

Example 1:

Input: c = 5

Output: true

Explanation: 1 * 1 + 2 * 2 = 5

Example 2:

Input: c = 3

Output: false

Constraints:

Solution

public class Solution {
    public boolean judgeSquareSum(int c) {
        int right = (int) Math.sqrt(c);
        int left = (int) Math.sqrt((double) c / 2);
        for (int i = left; i <= right; i++) {
            int j = (int) Math.sqrt(c - (double) (i * i));
            if (i * i + j * j == c) {
                return true;
            }
        }
        return false;
    }
}