solution.cpp

#include <iostream>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/push_relabel_max_flow.hpp>
#include <boost/graph/successive_shortest_path_nonnegative_weights.hpp>
#include <boost/graph/find_flow_cost.hpp>

typedef boost::adjacency_list_traits<boost::vecS, boost::vecS, boost::directedS> traits;
typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::no_property,
    boost::property<boost::edge_capacity_t, long,
        boost::property<boost::edge_residual_capacity_t, long,
            boost::property<boost::edge_reverse_t, traits::edge_descriptor,
                boost::property <boost::edge_weight_t, long> > > > > graph;

typedef boost::graph_traits<graph>::edge_descriptor             edge_desc;
typedef boost::graph_traits<graph>::vertex_descriptor           vertex_desc;
typedef boost::graph_traits<graph>::out_edge_iterator           out_edge_it;

class edge_adder {
 graph &G;

 public:
  explicit edge_adder(graph &G) : G(G) {}
  void add_edge(int from, int to, long capacity, long cost) {
    auto c_map = boost::get(boost::edge_capacity, G);
    auto r_map = boost::get(boost::edge_reverse, G);
    auto w_map = boost::get(boost::edge_weight, G);
    const edge_desc e = boost::add_edge(from, to, G).first;
    const edge_desc rev_e = boost::add_edge(to, from, G).first;
    c_map[e] = capacity;
    c_map[rev_e] = 0;
    r_map[e] = rev_e;
    r_map[rev_e] = e;
    w_map[e] = cost;
    w_map[rev_e] = -cost;
  }
};

void solve(){
  int n; std::cin >> n;
  graph G(n);
  edge_adder adder(G);
  vertex_desc src = boost::add_vertex(G);
  vertex_desc tgt = boost::add_vertex(G);
  int tots = 0;
  for (int i = 0; i < n; i++){
    int a, c; std::cin >> a >> c;
    adder.add_edge(src, i, a, c);
  }
  for (int i = 0; i < n; i++){
    int s, p; std::cin >> s >> p;
    adder.add_edge(i, tgt, s, 20-p);
    tots += s;
  }
  for (int i = 0; i < n - 1; i++){
    int v, e; std::cin >> v >> e;
    adder.add_edge(i, i + 1, v, e);
  }
  int sers = boost::push_relabel_max_flow(G, src, tgt);
  boost::successive_shortest_path_nonnegative_weights(G, src, tgt);
  int profit = sers*20 - boost::find_flow_cost(G);
  std::cout << (sers == tots ? "possible ":"impossible ") << sers << ' ' << profit << '\n';
}

int main(){
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);
  int t; std::cin >> t;
  while(t--) solve();
}