题解 | 绕距

#include <stdio.h>
#include<math.h>
int main(){
    int x1,x2,y1,y2;
    double e,m,n;
    scanf("%d %d",&x1,&y1);
    scanf("%d %d",&x2,&y2);
    e = sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
    m = abs(x1 - x2) + abs(y1 - y2);
    n = fabs(m - e);//浮点数求绝对值
    printf("%lf",n);
    return 0;
}