题解 | 牛牛的线段

#include <iostream>
using namespace std;

int main() {
	int x_1, y_1, x_2, y_2;
	scanf("%d%d%d%d", &x_1, &y_1, &x_2, &y_2);
	int delta_x = x_1 - x_2, delta_y = y_1 - y_2;
	printf("%d", delta_x * delta_x + delta_y * delta_y);
}