Submission #559128

#	Time	Username	Problem	Language	Result	Execution time	Memory
559128		cadmiumsky	Toy Train (IOI17_train)	C++14	100 / 100	1299 ms	3904 KiB

train

#include "train.h"
#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using uset = unordered_set<int>;

const int nmax = 5e3 + 5;
vector<int> g[nmax], t[nmax];
vector<int> own, charge, rez, degree;

int n, m;
uset S, notS;

int cnt = 0;
void solve(uset& V) {
  if(V.size() == 0)
    return;
  S.clear();
  notS.clear();
  for(auto x : V) {
    if(charge[x])
      S.insert(x);
    for(int i = 0; i < g[x].size(); i++) {
      if(V.count(g[x][i]) == 0)
        swap(g[x][i], g[x].back()), g[x].pop_back(), i--;
    }
    for(int i = 0; i < t[x].size(); i++) {
      if(V.count(t[x][i]) == 0)
        swap(t[x][i], t[x].back()), t[x].pop_back(), i--;
    }
  }
  if(S.size() == 0) {
    for(auto x : V)
      rez[x] = 0;
    return;
  }
  for(auto x : V) {
    if(charge[x])
      degree[x] = 0;
    if(own[x] == 1)
      degree[x] = 1;
    else
      degree[x] = g[x].size();
  }
  queue<int> que;
  function<void()> markall = [&]() {
    while (!que.empty()) {
      int node = que.front();
      for(auto x : t[node]) { 
        degree[x]--;
        if(degree[x] == 0 && !S.count(x))
          S.insert(x),
          que.push(x);
      }
      que.pop();
    }
    que = queue<int>();
    return;
  };
  for(auto x : S)
    que.push(x);
  markall();
  if(S.size() == V.size()) {
    for(auto x : V)
      rez[x] = 1;
    return;
  }
  for(auto x : V)
    if(S.count(x) == 0)
      notS.insert(x);
  for(auto x : V) {
    if(notS.count(x) == 1)
      degree[x] = 0;
    if(own[x] == 0)
      degree[x] = 1;
    else
      degree[x] = g[x].size();
  }
  swap(S, notS);
  for(auto x : S)
   que.push(x);
  markall();
  for(auto x : S)
    rez[x] = 0, // formality
    V.erase(x);
  solve(V);
}

std::vector<int> who_wins(std::vector<int> A, std::vector<int> R, std::vector<int> U, std::vector<int> V) {
	own = move(A);
	charge = move(R);
  n = own.size();
  m = U.size();
  degree.resize(n, 0);
  rez.resize(n, 0);
  for(int i = 0; i < m; i++)
    g[U[i]].push_back(V[i]),
    t[V[i]].push_back(U[i]);
  uset Vertex;
  for(int i = 0; i < n; i++)
    Vertex.insert(i);
  solve(Vertex);
  return rez;
}

Compilation message (stderr)

train.cpp: In function 'void solve(uset&)':
train.cpp:24:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     for(int i = 0; i < g[x].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
train.cpp:28:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |     for(int i = 0; i < t[x].size(); i++) {
      |                    ~~^~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 11 / 11
• Subtask 4: 11 / 11
• Subtask 5: 12 / 12
• Subtask 6: 51 / 51