Submission #97604

#	Time	Username	Problem	Language	Result	Execution time	Memory
97604		dalgerok	Pipes (CEOI15_pipes)	C++14	100 / 100	1198 ms	10660 KiB

pipes

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


const int N = 1e5 + 5;



int n, m;
int p[2][N];
int tin[N], fup[N], timer;

int E, Y[4 * N], lst[N], prv[4 * N];
void add_edge(int x, int y){
    Y[++E] = y;
    if(lst[x] == 0){
        lst[x] = E;
    }
    else{
        prv[E] = lst[x];
        lst[x] = E;
    }

    Y[++E] = x;
    if(lst[y] == 0){
        lst[y] = E;
    }
    else{
        prv[E] = lst[y];
        lst[y] = E;
    }
}

int dsu_get(int x, int v){
    return p[x][v] == v ? v : p[x][v] = dsu_get(x, p[x][v]);
}

void dfs(int v, int pr = 0){
    tin[v] = fup[v] = ++timer;
    bool was = false;
    for(int i = lst[v]; i != 0; i = prv[i]){
        int to = Y[i];
        if(to == pr){
            if(was){
                fup[v] = min(fup[v], tin[to]);
            }
            was = true;
            continue;
        }
        if(!tin[to]){
            dfs(to, v);
            if(fup[to] > tin[v]){
                cout << v << " " << to << "\n";
            }
            fup[v] = min(fup[v], fup[to]);
        }
        else{
            fup[v] = min(fup[v], tin[to]);
        }
    }

}
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n >> m;
    for(int i = 1; i <= n; i++){
        p[0][i] = p[1][i] = i;
    }
    for(int i = 1; i <= m; i++){
        int x, y;
        cin >> x >> y;
        if(dsu_get(0, x) == dsu_get(0, y)){
            if(dsu_get(1, x) == dsu_get(1, y)){
                continue;
            }
            p[1][dsu_get(1, x)] = dsu_get(1, y);
        }
        else{
            p[0][dsu_get(0, x)] = dsu_get(0, y);
        }
        add_edge(x, y);
    }
    for(int i = 1; i <= n; i++){
        if(!tin[i]){
            //cout << "KEK " << i << " " << tin[i] << "\n";
            dfs(i);
        }
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10