题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2001
注意输入时候的空格就可以了
#include<stdio.h>
#include<math.h>
int main()
{
double x1,x2,y1,y2;
while(scanf("%lf %lf %lf %lf",&x1,&y1,&x2,&y2)!=EOF)
{
getchar();
printf("%.2f
",sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1)));
}
}