Submission #948596

#	Time	Username	Problem	Language	Result	Execution time	Memory
948596		phone64bit	Commuter Pass (JOI18_commuter_pass)	C++17	0 / 100	238 ms	262144 KiB

commuter_pass

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

const int mxN = 1e5+10;


struct edge {
    int u, v;
};

struct path {
    int dest; ll w;
};

struct Q {
    int src; ll w;
    vector<edge> p;
    bool operator < (const Q&rhs) const {
        return w>rhs.w;
    }
};

vector<path> edges[mxN];
bitset<mxN> vs;
ll dp[mxN], k_dp[mxN], ans = 1e18;
int n,m,s,t,u,v; 
priority_queue<Q> pq;

int main() {
    for(int i=0; i<mxN; i++) dp[i]=1e18;
    scanf("%d%d%d%d%d%d", &n,&m,&s,&t,&u,&v);
    while(m--) {
        int u, v; ll w; scanf("%d%d%lld", &u, &v, &w);
        edges[u].push_back({v, w});
        edges[v].push_back({u, w});
    }
    pq.push({s, 0, {}});
    dp[s]=0;
    while(!pq.empty()) {
        auto [src, w, p] = pq.top();
        pq.pop();
        if(src==t) {
            for(auto x: p) edges[x.u].push_back({x.v, 0}), edges[x.v].push_back({x.u, 0});
            break;
        }
        for(auto c: edges[src]) {
            if(dp[c.dest]>c.w+w) {
                dp[c.dest]=c.w+w;
                p.push_back({src, c.dest});
                pq.push({c.dest, dp[c.dest], p});
                p.pop_back();
            }
        }
    }
    for(int i=0; i<mxN; i++) dp[i]=1e18;
    pq.push({u, 0});
    dp[u]=0;
    while(!pq.empty()) {
        auto [src, w, p] = pq.top();
        pq.pop();
        if(src==v) {
            printf("%lld", w);
            break;
        }
        for(auto c: edges[src]) {
            if(dp[c.dest]>c.w+w) {
                dp[c.dest]=c.w+w;
                pq.push({c.dest, dp[c.dest]});
            }
        }
    }
    return 0;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:32:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     scanf("%d%d%d%d%d%d", &n,&m,&s,&t,&u,&v);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:34:30: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         int u, v; ll w; scanf("%d%d%lld", &u, &v, &w);
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45