c – 有人可以告诉我为什么我的分数总是计算为零？

因为当我运行下面的函数时,结果是

Total lines = 6
Odd lines = 2
Percent odd lines = 0

bool count_odd_lines(string a,string b)
{
    ifstream in;
    ofstream out;
    in.open(a.c_str());
    out.open(b.c_str()); 
    string s;
    int count = 0;
    int odd =  0;  
    if (in && out)
    {
        while (getline(in,s))
        {
            count++;
            if (s.length() % 2 != 0) odd++;
        }
        out << "Total lines = " << count << endl;
        out << "Odd lines = " << odd << endl;
        double percent = odd/count;
        out << "Percent odd lines = " << setprecision(4) << percent <<endl;
        return true;
    }
    else return false; 
    in.close();
    out.close();
}