Submission #1090711

#	Time	Username	Problem	Language	Result	Execution time	Memory
1090711		trandangquang	날다람쥐 (JOI14_ho_t4)	C++14	100 / 100	97 ms	17032 KiB

2014_ho_t4

#include <bits/stdc++.h>
using namespace std;

const int N = 1e5+5;

using ll = long long;

int n, m, x, h[N]; ll mxh[N];
vector <pair <int, int>> adj[N];

int main() {
    cin.tie(0)->sync_with_stdio(0);

    cin >> n >> m >> x;
    for(int i = 1; i <= n; ++i) cin >> h[i];
    for(int i = 1; i <= m; ++i) {
        int u, v, w; cin >> u >> v >> w;
        if(h[u] >= w) adj[u].emplace_back(v, w);
        if(h[v] >= w) adj[v].emplace_back(u, w);
    }

    fill(mxh+1, mxh+1+n, -1e18);
    mxh[1] = x;

    priority_queue <pair <ll, int>> pq;
    pq.push({x, 1});

    while(pq.size()) {
        pair <ll, int> tp = pq.top(); pq.pop();
        ll hu = tp.first; int u = tp.second;

        if(hu < mxh[u]) continue;

        for(pair <int, int> i : adj[u]) {
            int v = i.first, w = i.second;
            ll hv = min(hu-w, (ll)h[v]);
            if(hv > mxh[v]) {
                mxh[v] = hv;
                pq.push({hv, v});
            }
        }
    }

    if(mxh[n] == (ll)-1e18) cout << "-1\n";
    else cout << x + h[n] - 2*mxh[n] << '\n';
}

• Subtask 1: 25 / 25
• Subtask 2: 25 / 25
• Subtask 3: 50 / 50