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Submission #386368

# Submission time Handle Problem Language Result Execution time Memory
386368 2021-04-06T13:12:22 Z FatihSolak Pipes (CEOI15_pipes) C++17
100 / 100
 1347 ms 14132 KB 
#include <bits/stdc++.h>
#define N 100005
using namespace std;
int par[N][2];
int find(int a,int val){
    if(par[a][val] == a)return a;
    return par[a][val] = find(par[a][val],val);
}
vector<int> adj[N];
bool merge(int a,int b,int val){
    int tmp1 = a,tmp2 = b;
    a = find(a,val);
    b = find(b,val);
    if(a == b)return 0;
    par[a][val] = b;
    adj[tmp1].push_back(tmp2);
    adj[tmp2].push_back(tmp1);
    return 1;
}
int n;
vector<int> tin, low;
int timer;
void IS_BRIDGE(int v,int a){
    cout << v << " " << a << endl;
}
void dfs(int v, int p = -1) {
    tin[v] = low[v] = timer++;
    for (int to : adj[v]) {
        if (to == p) continue;
        if (tin[to] != -1) {
            low[v] = min(low[v], tin[to]);
        } else {
            dfs(to, v);
            low[v] = min(low[v], low[to]);
            if (low[to] > tin[v] && find(v,1) != find(to,1))
                IS_BRIDGE(v, to);
        }
    }
}

void find_bridges() {
    timer = 0;
    tin.assign(N, -1);
    low.assign(N, -1);
    for (int i = 1; i <= n; ++i) {
        if (tin[i] == -1)
            dfs(i);
    }
}
void solve(){
    int m;
    cin >> n >> m;
    for(int i=1;i<=n;i++){
        par[i][0] = par[i][1] = i;
    }
    int l,r;
    for(int i=1;i<=m;i++){
        cin >> l >> r;
        if(!merge(l,r,0))
            merge(l,r,1);
    }
    find_bridges();
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    #ifdef Local
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
    #endif
    int t=1;
    //cin>>t;
    while(t--){
        solve();
    }
    #ifdef Local
    cout<<endl<<fixed<<setprecision(2)<<1000.0 * clock() / CLOCKS_PER_SEC<< " milliseconds ";
    #endif
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 3436 KB Output is correct
2 Correct 3 ms 3436 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 3948 KB Output is correct
2 Correct 7 ms 3692 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 119 ms 3948 KB Output is correct
2 Correct 114 ms 3692 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 192 ms 4588 KB Output is correct
2 Correct 220 ms 3948 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 337 ms 5944 KB Output is correct
2 Correct 299 ms 5612 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 455 ms 10860 KB Output is correct
2 Correct 389 ms 7404 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 701 ms 12012 KB Output is correct
2 Correct 642 ms 9124 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 908 ms 14132 KB Output is correct
2 Correct 873 ms 9196 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1129 ms 14056 KB Output is correct
2 Correct 1105 ms 9084 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1347 ms 13428 KB Output is correct
2 Correct 1262 ms 10648 KB Output is correct