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Submission #728073

# Submission time Handle Problem Language Result Execution time Memory
728073 2023-04-21T22:57:36 Z n0sk1ll Pipes (CEOI15_pipes) C++17
100 / 100
 968 ms 13348 KB 
#include <vector>
#include <iostream>
 
#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);cerr.tie(0)
 
using namespace std;
 
int up[2][100005];
 
int Up(bool c, int x)
{
    if (up[c][x]<0) return x;
    return up[c][x]=Up(c,up[c][x]);
}
 
bool dsu(bool c, int a, int b)
{
    a=Up(c,a),b=Up(c,b);
    if (a==b) return false;
    if (up[c][a]<up[c][b]) swap(a,b);
    up[c][b]+=up[c][a],up[c][a]=b;
    return true;
}
 
int par[100010];
int idx[100010];
int lowl[100010];
int nt;
vector<int> edge[100010];
 
void dfs(int x){
	idx[x] = lowl[x] = ++nt;
	bool cl = false;
	for(int y:edge[x]){
		if(par[x] == y && !cl){
			cl=true; continue;
		}
		if(!idx[y]){
			par[y]=x;
			dfs(y);
			lowl[x] = min(lowl[x], lowl[y]);
		} else lowl[x] = min(lowl[x], idx[y]);
	}
	if(par[x] && idx[x]==lowl[x]) cout<<x<<" "<<par[x]<<"\n";
}
 
int main()
{
    FAST;
 
    int n,m; cin>>n>>m;
    for (int c=0;c<2;c++) for (int i=1;i<=n;i++) up[c][i]=-1;
 
    while (m--)
    {
        int u,v; cin>>u>>v;
        if (dsu(0,u,v) || dsu(1,u,v)) edge[u].push_back(v),edge[v].push_back(u);
    }
 
    for (int i=1;i<=n;i++) if (up[0][i]<0) dfs(i);
}

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 6 ms 3156 KB Output is correct
2 Correct 4 ms 2900 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 85 ms 2972 KB Output is correct
2 Correct 80 ms 2852 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 141 ms 3644 KB Output is correct
2 Correct 166 ms 3256 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 255 ms 5228 KB Output is correct
2 Correct 202 ms 4924 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 320 ms 10188 KB Output is correct
2 Correct 280 ms 7620 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 494 ms 11236 KB Output is correct
2 Correct 455 ms 8780 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 640 ms 13336 KB Output is correct
2 Correct 596 ms 9904 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 812 ms 13348 KB Output is correct
2 Correct 776 ms 9896 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 968 ms 12696 KB Output is correct
2 Correct 882 ms 10444 KB Output is correct