测试数据很弱,double就可以过了
题目:http://acm.hdu.edu.cn/showproblem.php?pid=2001
#include <stdio.h>
#include <math.h>
int main()
{
double x1,x2,y1,y2;
while(scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2)!=EOF)
printf("%.2lf\n",sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)));
return 0;
}