32、fstream操作文件(c++)

#include<iostream>
#include<fstream>
using namespace std;
int  main(){
   ifstream fin("in.txt");
   ofstream fout("out.txt");
   int a,b,c;
   fin>>a>>b>>c;
   fout<<a*b*c<<endl;
   fin.close();
   fout.close(); 
}