oj.uz

Submission #860645

# Submission time Handle Problem Language Result Execution time Memory
860645 2023-10-13T15:21:57 Z Nursik Commuter Pass (JOI18_commuter_pass) C++14
100 / 100
 218 ms 31380 KB 
#include <stdio.h>

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <random>
#include <chrono>
#include <queue>
#include <functional>
#include <iostream>
#include <queue>
//#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define mp make_pair
#define f first
#define s second
#define ld long double

const ll maxn = 1e5 + 1, maxm = 1e7 + 1;
const ll mod = 1e9 + 7, mod2 = 998244353, inf = 1e9, block = 550, hb = 31, base = 1000050017;
const ld eps = 1e-9;

int n, m;
int s, t;
int ss, tt;
bool is[maxn];
int go[maxn];
ll ans = inf * inf, dp[maxn], dp2[maxn], dp3[maxn], was[maxn];
ll pd[maxn][2];
vector<pair<int, int>> g[maxn];
vector<int> g2[maxn], g3[maxn];
void dfsis(int v){
    if (v == t){
        is[v] = 1;
    }
    was[v] = 1;
    for (auto to : g2[v]){
        if (was[to] == 0){
            dfsis(to);
        }
        is[v] |= is[to];
    }
}

void dijkstra(){
    for (int i = 1; i <= n; ++i){
        dp[i] = inf * inf;
    }
    dp[s] = 0;
   // set<pair<ll, int>> setik;
    priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>> > setik;
    setik.push(mp(0, s));
    while (setik.size() > 0){
        pair<ll, int> cur = setik.top();
        setik.pop();
        ll cost = cur.f, v = cur.s;
        if (dp[v] < cost){
            continue;
        }
        for (auto to : g[v]){
            int nv = to.f, w = to.s;
            if (dp[nv] > cost + w){
                dp[nv] = cost + w;
                setik.push(mp(dp[nv], nv));
            }
        }
    }
    for (int i = 1; i <= n; ++i){
        for (auto to : g[i]){
            int nv = to.f, w = to.s;
            if (dp[i] > dp[nv]){
                continue;
            }
            if (dp[nv] == w + dp[i] && dp[i] < dp[nv]){
                g2[i].pb(nv);
            }
        }
    }
    dfsis(s);

    for (int i = 1; i <= n; ++i){
        g2[i].clear();
        for (auto to : g[i]){
            int nv = to.f, w = to.s;
            if (dp[i] > dp[nv]){
                continue;
            }
            if (dp[nv] == w + dp[i] && is[nv] == 1){
                g2[i].pb(nv);
            }
        }
    }
}
void dijkstra2(){
    for (int i = 1; i <= n; ++i){
        dp2[i] = inf * inf;
    }
    dp2[ss] = 0;
  //  set<pair<ll, int>> setik;
    priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>> > setik;
    setik.push(mp(0, ss));
    while (setik.size() > 0){
        pair<ll, int> cur = setik.top();
        setik.pop();
        ll cost = cur.f, v = cur.s;
        if (dp2[v] < cost){
            continue;
        }
        for (auto to : g[v]){
            int nv = to.f, w = to.s;
            if (dp2[nv] > cost + w){
                dp2[nv] = cost + w;
                setik.push(mp(dp2[nv], nv));
            }
        }
    }
}
void dijkstra3(){
    for (int i = 1; i <= n; ++i){
        dp3[i] = inf * inf;
    }
    dp3[tt] = 0;
    priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>> > setik;
    setik.push(mp(0, tt));
    while (setik.size() > 0){
        pair<ll, int> cur = setik.top();
        setik.pop();
        ll cost = cur.f, v = cur.s;
        if (dp3[v] < cost){
            continue;
        }
        for (auto to : g[v]){
            int nv = to.f, w = to.s;
            if (dp3[nv] > cost + w){
                dp3[nv] = cost + w;
                setik.push(mp(dp3[nv], nv));
            }
        }
    }
}

void backdfs(int v){
    for (int i = 1; i <= n; ++i){
        for (auto to : g2[i]){
            go[i] += 1;
            g3[to].pb(i);
        }
        pd[i][0] = inf * inf;
        pd[i][1] = inf * inf;
    }

    queue<int> q;
    q.push(v);
    while (q.size() > 0){
        int u = q.front();
        q.pop();
        pd[u][0] = min(pd[u][0], dp3[u]);
        pd[u][1] = min(pd[u][1], dp2[u]);

        ans = min(ans, pd[u][0] + dp2[u]);
        ans = min(ans, pd[u][1] + dp3[u]);
        for (auto to : g3[u]){
            go[to] -= 1;
            pd[to][0] = min(pd[to][0], pd[u][0]);
            pd[to][1] = min(pd[to][1], pd[u][1]);
            if (go[to] == 0){
                q.push(to);
            }
        }
    }
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    cin >> s >> t;
    cin >> ss >> tt;
    
    for (int i = 1; i <= m; ++i){
        int a, b, c;
        cin >> a >> b >> c;
        g[a].pb(mp(b, c));
        g[b].pb(mp(a, c));
    }
    dijkstra();
    dijkstra2();
    dijkstra3();
    backdfs(t);
    ans = min(ans, dp2[tt]);
    cout << ans << '\n';
}

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 175 ms 22860 KB Output is correct
2 Correct 159 ms 22556 KB Output is correct
3 Correct 214 ms 31380 KB Output is correct
4 Correct 151 ms 26924 KB Output is correct
5 Correct 156 ms 26588 KB Output is correct
6 Correct 162 ms 26668 KB Output is correct
7 Correct 164 ms 26944 KB Output is correct
8 Correct 164 ms 26712 KB Output is correct
9 Correct 168 ms 26316 KB Output is correct
10 Correct 169 ms 25808 KB Output is correct
11 Correct 67 ms 25680 KB Output is correct
12 Correct 164 ms 26728 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 168 ms 25032 KB Output is correct
2 Correct 178 ms 25300 KB Output is correct
3 Correct 174 ms 25244 KB Output is correct
4 Correct 170 ms 25208 KB Output is correct
5 Correct 218 ms 25276 KB Output is correct
6 Correct 165 ms 27116 KB Output is correct
7 Correct 177 ms 29612 KB Output is correct
8 Correct 175 ms 25184 KB Output is correct
9 Correct 174 ms 25224 KB Output is correct
10 Correct 170 ms 25224 KB Output is correct
11 Correct 70 ms 24656 KB Output is correct
12 Correct 163 ms 27492 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 11612 KB Output is correct
2 Correct 3 ms 11100 KB Output is correct
3 Correct 2 ms 10844 KB Output is correct
4 Correct 13 ms 12892 KB Output is correct
5 Correct 7 ms 11952 KB Output is correct
6 Correct 2 ms 10840 KB Output is correct
7 Correct 3 ms 10844 KB Output is correct
8 Correct 3 ms 11100 KB Output is correct
9 Correct 3 ms 10844 KB Output is correct
10 Correct 7 ms 11864 KB Output is correct
11 Correct 3 ms 10844 KB Output is correct
12 Correct 2 ms 10844 KB Output is correct
13 Correct 3 ms 11100 KB Output is correct
14 Correct 2 ms 10844 KB Output is correct
15 Correct 2 ms 10844 KB Output is correct

Subtask #4
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 175 ms 22860 KB Output is correct
2 Correct 159 ms 22556 KB Output is correct
3 Correct 214 ms 31380 KB Output is correct
4 Correct 151 ms 26924 KB Output is correct
5 Correct 156 ms 26588 KB Output is correct
6 Correct 162 ms 26668 KB Output is correct
7 Correct 164 ms 26944 KB Output is correct
8 Correct 164 ms 26712 KB Output is correct
9 Correct 168 ms 26316 KB Output is correct
10 Correct 169 ms 25808 KB Output is correct
11 Correct 67 ms 25680 KB Output is correct
12 Correct 164 ms 26728 KB Output is correct
13 Correct 168 ms 25032 KB Output is correct
14 Correct 178 ms 25300 KB Output is correct
15 Correct 174 ms 25244 KB Output is correct
16 Correct 170 ms 25208 KB Output is correct
17 Correct 218 ms 25276 KB Output is correct
18 Correct 165 ms 27116 KB Output is correct
19 Correct 177 ms 29612 KB Output is correct
20 Correct 175 ms 25184 KB Output is correct
21 Correct 174 ms 25224 KB Output is correct
22 Correct 170 ms 25224 KB Output is correct
23 Correct 70 ms 24656 KB Output is correct
24 Correct 163 ms 27492 KB Output is correct
25 Correct 7 ms 11612 KB Output is correct
26 Correct 3 ms 11100 KB Output is correct
27 Correct 2 ms 10844 KB Output is correct
28 Correct 13 ms 12892 KB Output is correct
29 Correct 7 ms 11952 KB Output is correct
30 Correct 2 ms 10840 KB Output is correct
31 Correct 3 ms 10844 KB Output is correct
32 Correct 3 ms 11100 KB Output is correct
33 Correct 3 ms 10844 KB Output is correct
34 Correct 7 ms 11864 KB Output is correct
35 Correct 3 ms 10844 KB Output is correct
36 Correct 2 ms 10844 KB Output is correct
37 Correct 3 ms 11100 KB Output is correct
38 Correct 2 ms 10844 KB Output is correct
39 Correct 2 ms 10844 KB Output is correct
40 Correct 140 ms 26656 KB Output is correct
41 Correct 152 ms 25644 KB Output is correct
42 Correct 157 ms 25972 KB Output is correct
43 Correct 70 ms 27220 KB Output is correct
44 Correct 69 ms 27220 KB Output is correct
45 Correct 165 ms 28180 KB Output is correct
46 Correct 180 ms 28076 KB Output is correct
47 Correct 172 ms 27168 KB Output is correct
48 Correct 71 ms 24656 KB Output is correct
49 Correct 134 ms 27884 KB Output is correct
50 Correct 152 ms 27316 KB Output is correct
51 Correct 146 ms 28104 KB Output is correct