C++ 输入输出流的引用调用

#include<fstream>

using namespace std;

void print_row(ofstream& out, char c, int n);

int main()
{
ofstream outfile;
outfile.open("out2.txt");
print_row(outfile, 'c', 10);
outfile.close();
return 0;
}

void print_row(ofstream& out, char c, int n)
{
for(int i=0;i<n;i++)
out<<c<<endl;
}