#include <stdio.h>
#include <math.h>

int main() {
    int x1, x2;
    int y1,y2;
    int s;
    scanf("%d %d", &x1, &y1);
    scanf("%d %d", &x2, &y2);
    
    s=pow((x1-x2),2)+pow((y1-y2),2);
    printf("%d",s);
    
    return 0;
}

有点粗心，仔细看题目！！！