谁知道printf("%.2lf\n",q);他只输出0.00,用cout还好
#include<bits/stdc++.h>
using namespace std;
int main(){
int a,b,c,d,e,f,q,w,o;
cin>>a>>b>>c>>d>>e>>f;
q=sqrt((a-c)*(a-c)+(b-d)*(b-d));
w=sqrt((a-e)*(a-e)+(b-f)*(b-f));
o=sqrt((c-e)*(c-e)+(d-f)*(d-f));
q=q+w+o;
printf("%.2lf\n",q);
return 0;
}