#include #include #include int main() { procbuf pb; pb.open("sort -f", ios::out); ostream opb(&pb); string line; while (getline(cin, line)) { size_t pos; if ( line.length() == 0 || (pos = line.find_first_not_of(" \t")) != string::npos && line[pos] == '#' ) continue; opb << line << '\n'; } }