hdu 4493 卡輸入輸出

題目地址： http://acm.hdu.edu.cn/showproblem.php?pid=4493

一個double 如果就用cout 貌似會用科學計數法；

#include<iostream>using namespace std;int x1(double k){   k*=10;   return (int)k%10;}int x2(double k){   k*=100;   return (int)k%10;}int x3(double k){   k*=1000;   return (int)k%10;}int main(){   int T;   cin>>T;   while(T--)    {       double ans=0;       for(int i=0;i<12;i++)         {             double temp;             cin>>temp;             ans+=temp;         }        ans/=12;      if(x3(ans)>=5)  ans+=0.01;      cout<<"$"<<(long long )ans;      int a1=x1(ans);      int a2=x2(ans);       if(a1==0&&a2==0)   cout<<endl;      else if(a1!=0&&a2==0)  cout<<"."<<a1<<endl;      else cout<<"."<<a1<<a2<<endl;   //   cout<<"$"<<ans<<endl;   //這樣就會錯    }}