杭电多校 Rikka with Square Numbers 费马平方和定理

👨‍🏫 Rikka with Square Numbers

🧀 参考题解

🍻 AC code

import java.util.Scanner;public class Main
{static boolean isSqu(int x){int t = (int) Math.sqrt(x);return t * t == x;}public static void main(String[] args){Scanner sc = new Scanner(System.in);int T = sc.nextInt();while (T-- > 0){int a = sc.nextInt();int b = sc.nextInt();int d = (a - b) > 0 ? a - b : b - a;if (isSqu(d))System.out.println(1);else if (d % 4 == 0 || d % 2 == 1){System.out.println(2);} else{boolean flag = false;for (int i = 1; i * i < d; i++)if (isSqu(d - i * i))flag = true;if (flag)System.out.println(2);else{System.out.println(3);}}}}
}