Course Schedule

input/code.cpp: In function 'int main()':
input/code.cpp:30:20: warning: unused variable 'cost' [-Wunused-variable]
   30 |     ll start, end, cost;
      |                    ^~~~

#include <iostream>
#include <vector>
#define ll unsigned long long

int search(ll node, std::vector<char> &cheked,
           std::vector<std::vector<int>> &connMap, std::vector<ll> &retArr) {
  if (cheked[node] == 1)
    return -1;
  if (cheked[node] == 2)
    return 0;
  cheked[node] = 1;
  for (int neighbour : connMap[node]) {
    int ret = search(neighbour, cheked, connMap, retArr);
    if (ret == -1) {
      return -1;
    }
  }
  retArr.push_back(node);
  cheked[node] = 2;
  return 0;
}

int main() {
  ll courseCount, reqCount;
  std::cin >> courseCount;
  std::cin >> reqCount;

  std::vector<std::vector<int>> connMap(courseCount);
  for (ll ii = 0; ii < reqCount; ii++) {
    ll start, end, cost;
    std::cin >> start;
    std::cin >> end;
    connMap[start - 1].push_back(end - 1);
  }

  std::vector<char> cheked(courseCount, 0);
  std::vector<ll> retArr;
  for (ll ii = 0; ii < courseCount; ii++) {
    int ret = search(ii, cheked, connMap, retArr);
    if (ret == -1) {
      std::cout << "IMPOSSIBLE" << std::endl;
      return 0;
    }
  }
  for (ll ii = retArr.size() - 1; ii > 0; ii--) {
    std::cout << retArr[ii] + 1 << " ";
  }
  std::cout << retArr[0] + 1 << std::endl;
  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED