Submission #100617

#	Time	Username	Problem	Language	Result	Execution time	Memory
100617		doowey	Pipes (CEOI15_pipes)	C++14	90 / 100	1125 ms	11860 KiB

pipes

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

const int N = (int)1e5 + 9;

struct DSU{
    int pi[N];
    void Init(){
        for(int i = 0 ; i < N; i ++ )
            pi[i] = i;
    }
    int fin(int node){
        if(node == pi[node])
            return node;
        return pi[node] = fin(pi[node]);
    }
    bool unite(int a, int b){
        a = fin(a);
        b = fin(b);
        if(a==b)
            return false;
        pi[a] = b;
        return true;
    }
};

DSU A, B;

// all this memory bullsh*t
int nod[N * 4];
int prv[N * 4];
int tin[N];
int las[N];
int p;


void init(){
    for(int i =0 ; i < N; i ++ )
        las[i] = -1, tin[i] = -1;
    for(int i = 0 ;i < N * 4 ;i ++ )
        prv[i] = -1, nod[i] = -1;
}

void addedg(int a, int b){
    prv[p] = las[a];
    nod[p] = b;
    las[a] = p;
    p ++ ;
}

void EDGE(int a, int b){
    addedg(a, b);
    addedg(b, a);
}

int low[N];

int timer;

void dfs(int node, int par){
    tin[node] = timer ++ ;
    low[node] = tin[node];
    for(int i = las[node]; i != -1; i = prv[i]){
        if(nod[i] == par)
            continue;
        if(tin[nod[i]] != -1){
            low[node] = min(low[node], tin[nod[i]]);
        }
        else{
            dfs(nod[i], node);
            low[node] = min(low[node], low[nod[i]]);
            if(tin[node] < low[nod[i]] && B.fin(nod[i]) != B.fin(node)){
                cout << node << " " << nod[i] << "\n";
            }
        }
    }
}

int main(){
    fastIO;
    init();
    A.Init();
    B.Init();
    int n, m;
    cin >> n >> m;
    int u, v;
    for(int i =0 ; i < m ; i ++ ){
        cin >> u >> v;
        if(A.unite(u,v)){
            EDGE(u,v);
        }
        else if(B.unite(u, v)){
            EDGE(u,v);
        }
    }
    dfs(1,-1);

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 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