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Submission #669381

# Submission time Handle Problem Language Result Execution time Memory
669381 2022-12-06T10:39:05 Z ShaShi Pipes (CEOI15_pipes) C++17
100 / 100
 978 ms 16216 KB 
#include <bits/stdc++.h>
#define lint long long int
#define dint long double
#define ll long long
#define endl "\n"
#define pii pair<int, int>
#define pb push_back
#define F first
#define S second

using namespace std;

const int MOD = (int)1e9 + 23;
const int MAXN = (int)1e5 + 23;
const int MAX_LOG = 17 + 1;
const int INF = (int)1e9 + 23;

int n, m, tmp, tmp2, u, v;
int par1[MAXN], par2[MAXN], sz1[MAXN], sz2[MAXN], h[MAXN], dp[MAXN], googool[MAXN+MAXN], p[MAXN];
vector<pii> adj[MAXN];
bool seen[MAXN];

int get_par1(int v) {
    return (par1[v] == -1? v : par1[v] = get_par1(par1[v]));
}

int get_par2(int v) {
    return (par2[v] == -1? v : par2[v] = get_par2(par2[v]));
}

bool merge1(int u, int v) {
    u = get_par1(u);
    v = get_par1(v);

    if (u == v) return 0;

    par1[u] = v;

    return 1;
}

bool merge2(int u, int v) {
    u = get_par2(u);
    v = get_par2(v);

    if (u == v) return 0;

    par2[u] = v;

    return 1;
}

void DFS(int v) {
	seen[v] = 1;

	for(auto w:adj[v]) {
        int u = w.F;
        int ind=w.S;
        
        if(seen[u]){
			if(googool[ind] == 0 && h[u] < (h[v])){
				dp[v]++;
				dp[u]--;
			}
			continue;
		}

		h[u] = h[v] + 1; 
		p[u] = v;
		googool[ind] = 1; 
		DFS(u);
		dp[v] += dp[u];
	}
}

int32_t main() {
	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    
    cin >> n >> m;

    fill(par1, par1+n+1, -1);
    fill(par2, par2+n+1, -1);
    tmp = 1;

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

        if (merge1(u, v)) {
            adj[u].pb({v, tmp});
            adj[v].pb({u, tmp});
            tmp++;
        } else if (merge2(u, v)) {
            adj[u].pb({v, tmp});
            adj[v].pb({u, tmp});
            tmp++;
        }
    }

    for (int i=1; i<=n; i++) {
        if (!seen[i]) {
            DFS(i);
        }
    }

    for (int i=1; i<=n ; i++) {
		if (!dp[i] && p[i]) {
			cout << p[i] << " " << i << endl;
		}
	}

    
    


    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 3272 KB Output is correct
2 Correct 5 ms 3028 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 93 ms 3188 KB Output is correct
2 Correct 84 ms 2940 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 176 ms 4008 KB Output is correct
2 Correct 160 ms 3604 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 263 ms 5832 KB Output is correct
2 Correct 203 ms 5468 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 342 ms 12256 KB Output is correct
2 Correct 297 ms 9336 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 541 ms 13664 KB Output is correct
2 Correct 510 ms 10188 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 698 ms 16176 KB Output is correct
2 Correct 672 ms 12152 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 835 ms 16216 KB Output is correct
2 Correct 752 ms 12232 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 978 ms 15560 KB Output is correct
2 Correct 871 ms 12148 KB Output is correct