题解 | #牛牛的线段#

#include <stdio.h>

int main() {
    int x1 = 0;
    int y1 = 0;
    int x2 = 0;
    int y2 = 0;

    scanf("%d %d", &x1, &y1);
    scanf("%d %d", &x2, &y2);
    printf("%d\n", (x1 - x2) * (x1 - x2)  + (y1 - y2) * (y1 - y2));

    return 0;
}