for (size_t i = 0; i < inputs.size(); ++i) {
InputStats stats = inputs[i]->get_stats();
fprintf(fp, "%s %llu %llu", stats.url.c_str(),
for (size_t i = 0; i < inputs.size(); ++i) {
InputStats stats = inputs[i]->get_stats();
fprintf(fp, "%s %llu %llu", stats.url.c_str(),