Submission #472315

#	Time	Username	Problem	Language	Result	Execution time	Memory
472315		elgamalsalman	Toll (BOI17_toll)	C++14	0 / 100	3052 ms	7956 KiB

toll

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second

typedef long long ll;
typedef pair<ll, ll> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef vector<vii> vvii;

ll k, n, m, o, dp[50050];
vvii  adj;

void getToll(ll u, ll v) {
  //cerr << "// getToll(" << u << ", " << v << ")\n";
  if (dp[u] != -1) return;
  if (u == v) { dp[u] = 0; return; }
  if (u/5 >= v/5) { dp[u] = 1e9; return; }

  ll minToll = 1e9;
  for (ii edge : adj[u]) {
    getToll(edge.fi, v);
    if (dp[edge.fi] >= 1e9) continue;
    ll currToll = dp[edge.fi] + edge.se;
    if (currToll < minToll) minToll = currToll;
  }

  dp[u] = minToll;
  //cerr << "// " <<  dp[u] << '\n';
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cin >> k >> n >> m >> o;
  adj.assign(n + 20, vii());
  for (ll i = 0; i < m; i++) {
    ll a, b, t;
    cin >> a >> b >> t;
    adj[a].push_back({b, t});
  }
  
  for (ll i = 0; i < o; i++) {
    memset(dp, -1, sizeof dp);
    ll a, b;
    cin >> a >> b;
    getToll(a, b);
    cout << (dp[a] >= 1e9 ? -1 : dp[a]) << '\n';
  }
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 10
• Subtask 3: 0 / 8
• Subtask 4: 0 / 31
• Subtask 5: 0 / 44