Submission #1145202

#	Time	Username	Problem	Language	Result	Execution time	Memory
1145202		mgl_diamond	Robot (JOI21_ho_t4)	C++17	34 / 100	3095 ms	58792 KiB

Main

#include <bits/stdc++.h>
 
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
 
#define foru(i, l, r) for(int i=(l); i<=(r); ++i)
#define ford(i, l, r) for(int i=(l); i>=(r); --i)
#define fore(x, v) for(auto &x : v)
#define all(x) (x).begin(), (x).end()
#define siz(x) (int)(x).size()
#define pow2(x) (1ll << (x))
#define on(mask, x) ((mask >> x & 1) == 1)
#define off(mask, x) ((mask >> x & 1) == 0)
#define mp make_pair
#define vec vector
#define ar array
#define fi first
#define se second
#define pii pair<int, int>
#define out(x) cout << #x << " " << x << "\n"
template<class T> bool ckmin(T &a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<class T> bool ckmax(T &a, T b) { if (a < b) { a = b; return 1; } return 0; }
 
void setIO() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  #define task "input"
  if (fopen(task".inp", "r")) {
    freopen(task".inp", "r", stdin);
    freopen(task".out", "w", stdout);
  }
}

const ll LINF = 1e18+18;
const int INF = 1e9+9;
const int N = 2e5+5;
int n, m;

struct Edge {
  int a[2];
  ll c, p;
  Edge (int _u=0, int _v=0, int _c=0, ll _p=0) {
    a[0] = _u;
    a[1] = _v;
    c = _c;
    p = _p;
  }
  int other(int u) {
    return a[0]^a[1]^u;
  }
};

vector<Edge> edges;
vector<int> adj[N];
map<int, ll> color[N];
map<int, ll> dp[N];
ll sum[N][2];

int main() {
  setIO();

  cin >> n >> m;

  for (int i = 0; i < m; ++i) {
    int u, v, c, p;
    cin >> u >> v >> c >> p;
    if (u > v) swap(u, v);
    adj[u].push_back(siz(edges));
    adj[v].push_back(siz(edges));
    edges.emplace_back(u, v, c, p);
    color[u][c] += p;
    color[v][c] += p;
  }

  priority_queue<pair<ll, pair<int, int>>> pq;
  dp[1][0] = 0;
  pq.push({0, {1, 0}});

  while (!pq.empty()) {
    auto top = pq.top();
    pq.pop();

    ll w = -top.fi;
    int u = top.se.fi, lst_c = top.se.se;

    if (w != dp[u][lst_c]) continue;
    if (u == n && lst_c == 0) {
      cout << w;
      return 0;
    }

    if (lst_c == 0) {
      for (int i : adj[u]) {
        int v = edges[i].other(u);
        ll cost = w + min(color[u][edges[i].c] - edges[i].p, edges[i].p);

        if (dp[v].find(0) == dp[v].end()) dp[v][0] = LINF;
        if (dp[v].find(edges[i].c) == dp[v].end()) dp[v][edges[i].c] = LINF;

        if (ckmin(dp[v][0], cost)) {
          pq.push({-dp[v][0], {v, 0}});
        }
        if (ckmin(dp[v][edges[i].c], w)) {
          pq.push({-dp[v][edges[i].c], {v, edges[i].c}});
        }
      }
    }
    else {
      for (int i : adj[u]) {
        int v = edges[i].other(u);
        if (edges[i].c != lst_c) continue;
        if (dp[v].find(0) == dp[v].end()) dp[v][0] = LINF;
        if (ckmin(dp[v][0], w + color[u][edges[i].c] - edges[i].p)) {
          pq.push({-dp[v][0], {v, 0}});
        }
      }
    }
  }

  cout << -1;
}

Compilation message (stderr)

Main.cpp: In function 'void setIO()':
Main.cpp:31:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |     freopen(task".inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     freopen(task".out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 34 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42