oj.uz

Submission #1105325

# Submission time Handle Problem Language Result Execution time Memory
1105325 2024-10-26T07:29:48 Z tuannm Hotspot (NOI17_hotspot) C++17
100 / 100
 526 ms 1616 KB 
#include<bits/stdc++.h>
#define ii pair<int, int>
#define ll pair<long long, long long>
#define fi first
#define se second
#define pb push_back
using namespace std;
const int mod[2] = {1000000007, 998244353};
const int N = 5e3 + 1;
const string NAME = "traincentre";
int n, m, k;
vector<int> adj[N];
int d[2][N], cnt[2][N];
int q[N];
long double ans[N];

void BFS(int id, int s){
    for(int i = 0; i < n; ++i)
        d[id][i] = N, cnt[id][i] = 0;

    d[id][s] = 0;
    cnt[id][s] = 1;

    int l = 1, r = 1;
    q[1] = s;

    while(l <= r){
        int u = q[l++];

        for(int v : adj[u]){
            if(d[id][v] > d[id][u] + 1)
                d[id][v] = d[id][u] + 1, cnt[id][v] = cnt[id][u], q[++r] = v;
            else if(d[id][v] == d[id][u] + 1)
                cnt[id][v] += cnt[id][u];
        }
    }
}

void inp(){
    cin >> n >> m;
    for(int i = 1; i <= m; ++i){
        int u, v;
        cin >> u >> v;

        adj[u].pb(v);
        adj[v].pb(u);
    }
}

void solve(){
    cin >> k;

    while(k--){
        int a, b;
        cin >> a >> b;

        BFS(0, a);
        BFS(1, b);

        for(int w = 0; w < n; ++w)
            if(d[0][w] + d[1][w] == d[0][b])
                ans[w] += (long double) (1LL * cnt[0][w] * cnt[1][w]) / (1.0 * cnt[0][b]);
    }

    int res = -1;
    for(int i = 0; i < n; ++i)
        if(res == -1 || ans[i] > ans[res])
            res = i;

    cout << res;
}

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

    if(fopen((NAME + ".inp").c_str(), "r")){
        freopen((NAME + ".inp").c_str(), "r", stdin);
        freopen((NAME + ".out").c_str(), "w", stdout);
    }

    inp();
    solve();
}

Compilation message

hotspot.cpp: In function 'int main()':
hotspot.cpp:79:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |         freopen((NAME + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
hotspot.cpp:80:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |         freopen((NAME + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct
8 Correct 1 ms 592 KB Output is correct
9 Correct 1 ms 592 KB Output is correct
10 Correct 1 ms 592 KB Output is correct
11 Correct 1 ms 592 KB Output is correct
12 Correct 1 ms 592 KB Output is correct
13 Correct 1 ms 592 KB Output is correct
14 Correct 1 ms 592 KB Output is correct

Subtask #3
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct
8 Correct 1 ms 592 KB Output is correct
9 Correct 2 ms 592 KB Output is correct
10 Correct 2 ms 592 KB Output is correct
11 Correct 3 ms 592 KB Output is correct
12 Correct 1 ms 592 KB Output is correct
13 Correct 1 ms 764 KB Output is correct
14 Correct 2 ms 628 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct
8 Correct 1 ms 592 KB Output is correct
9 Correct 1 ms 592 KB Output is correct
10 Correct 1 ms 592 KB Output is correct
11 Correct 1 ms 592 KB Output is correct
12 Correct 1 ms 592 KB Output is correct
13 Correct 1 ms 592 KB Output is correct
14 Correct 1 ms 592 KB Output is correct
15 Correct 1 ms 592 KB Output is correct
16 Correct 2 ms 592 KB Output is correct
17 Correct 2 ms 592 KB Output is correct
18 Correct 3 ms 592 KB Output is correct
19 Correct 1 ms 592 KB Output is correct
20 Correct 1 ms 764 KB Output is correct
21 Correct 2 ms 628 KB Output is correct
22 Correct 1 ms 592 KB Output is correct
23 Correct 1 ms 592 KB Output is correct
24 Correct 2 ms 592 KB Output is correct
25 Correct 2 ms 592 KB Output is correct
26 Correct 2 ms 592 KB Output is correct
27 Correct 1 ms 592 KB Output is correct
28 Correct 2 ms 592 KB Output is correct

Subtask #5
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct
8 Correct 1 ms 592 KB Output is correct
9 Correct 1 ms 592 KB Output is correct
10 Correct 1 ms 592 KB Output is correct
11 Correct 1 ms 592 KB Output is correct
12 Correct 1 ms 592 KB Output is correct
13 Correct 1 ms 592 KB Output is correct
14 Correct 1 ms 592 KB Output is correct
15 Correct 2 ms 592 KB Output is correct
16 Correct 1 ms 592 KB Output is correct
17 Correct 4 ms 592 KB Output is correct
18 Correct 2 ms 592 KB Output is correct
19 Correct 3 ms 592 KB Output is correct
20 Correct 2 ms 760 KB Output is correct
21 Correct 1 ms 592 KB Output is correct

Subtask #6
36.0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 592 KB Output is correct
2 Correct 1 ms 592 KB Output is correct
3 Correct 1 ms 592 KB Output is correct
4 Correct 1 ms 760 KB Output is correct
5 Correct 1 ms 592 KB Output is correct
6 Correct 1 ms 592 KB Output is correct
7 Correct 1 ms 592 KB Output is correct
8 Correct 1 ms 592 KB Output is correct
9 Correct 1 ms 592 KB Output is correct
10 Correct 1 ms 592 KB Output is correct
11 Correct 1 ms 592 KB Output is correct
12 Correct 1 ms 592 KB Output is correct
13 Correct 1 ms 592 KB Output is correct
14 Correct 1 ms 592 KB Output is correct
15 Correct 1 ms 592 KB Output is correct
16 Correct 2 ms 592 KB Output is correct
17 Correct 2 ms 592 KB Output is correct
18 Correct 3 ms 592 KB Output is correct
19 Correct 1 ms 592 KB Output is correct
20 Correct 1 ms 764 KB Output is correct
21 Correct 2 ms 628 KB Output is correct
22 Correct 1 ms 592 KB Output is correct
23 Correct 1 ms 592 KB Output is correct
24 Correct 2 ms 592 KB Output is correct
25 Correct 2 ms 592 KB Output is correct
26 Correct 2 ms 592 KB Output is correct
27 Correct 1 ms 592 KB Output is correct
28 Correct 2 ms 592 KB Output is correct
29 Correct 2 ms 592 KB Output is correct
30 Correct 1 ms 592 KB Output is correct
31 Correct 4 ms 592 KB Output is correct
32 Correct 2 ms 592 KB Output is correct
33 Correct 3 ms 592 KB Output is correct
34 Correct 2 ms 760 KB Output is correct
35 Correct 1 ms 592 KB Output is correct
36 Correct 48 ms 592 KB Output is correct
37 Correct 101 ms 848 KB Output is correct
38 Correct 526 ms 1244 KB Output is correct
39 Correct 290 ms 1104 KB Output is correct
40 Correct 53 ms 1016 KB Output is correct
41 Correct 316 ms 1104 KB Output is correct
42 Correct 461 ms 1616 KB Output is correct
43 Correct 21 ms 592 KB Output is correct
44 Correct 18 ms 592 KB Output is correct