build-order-filter.cc

#include <cstdio>
#include <iostream>
#include <map>
#include <string>
#include <vector>

int main(int argc, char* argv[]) {
  std::string line;
  std::vector<std::string> prelude, postlude;
  std::map<int, std::vector<std::string>> groups;
  while (std::getline(std::cin, line)) {
    int proj_idx;
    if (1 == sscanf(line.c_str(), "%d>", &proj_idx)) {
      groups[proj_idx].push_back(line);
    }
    else {
      if (groups.empty()) {
        prelude.push_back(line);
      }
      else {
        postlude.push_back(line);
      }
    }
  }
  for (auto const& line : prelude) {
    std::cout << line << std::endl;
  }
  for (auto const& g : groups) {
    for (auto const& line : g.second) {
      std::cout << line << std::endl;
    }
  }
  for (auto const& line : postlude) {
    std::cout << line << std::endl;
  }
}