poj1004

#include <iostream>#include <stdio.h>using namespace std;int main(){ double sum,mou;   int i;  // freopen("in.txt","r",stdin);   sum=0;   for (i=1;i<=12;i++)   {        cin>>mou;        sum+=mou;   }   sum=sum/12;   cout<<'$';   printf("%.2f\n",sum);    return 0;}

求平均数