北大OJ_1004题：Financial Management

#include <iostream>
#include <iomanip>

using namespace std;

int main()
{
  double dVal = 0.0;
  int nCount = 12;
  double dSum = 0.0;
  while( nCount > 0 )
  {
    cin >> dVal;
    dSum += dVal;
    --nCount;
  }
  cout << setiosflags(ios::fixed) << setprecision(2) << "$" << dSum/12.0 << endl;
  return 0;
}

作者：山丘儿