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
Example 3:
Input: c = 4 Output: true
Example 4:
Input: c = 2 Output: true
Example 5:
Input: c = 1 Output: true
Constraints:
0 <= c <= 231 - 1struct Solution;
impl Solution {
fn judge_square_sum(c: i32) -> bool {
if c == 0 {
return true;
}
let x = (c as f64).sqrt() as i32;
for a in 0..=x {
let bb = c - a * a;
let b = (bb as f64).sqrt() as i32;
if bb == b * b {
return true;
}
}
false
}
}
#[test]
fn test() {
assert_eq!(Solution::judge_square_sum(5), true);
assert_eq!(Solution::judge_square_sum(3), false);
assert_eq!(Solution::judge_square_sum(2_147_483_646), false);
}