题解 | #牛牛的线段#

#include <stdio.h>

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

easy