oj.uz

Submission #591993

# Submission time Handle Problem Language Result Execution time Memory
591993 2022-07-08T10:58:35 Z andrei_boaca Pipes (CEOI15_pipes) C++14
80 / 100
 4976 ms 32112 KB 
#include <bits/stdc++.h>

using namespace std;
typedef pair<int,int> pii;
vector<vector<int>> muchii;
int comp[100005],myroot[100005],dp[19][100005],val[100005],par[100005],niv[100005],lg[100005];
int n,m;
int what;
int LCA(int a,int b)
{
    if(niv[a]<niv[b])
        swap(a,b);
    int dif=niv[a]-niv[b];
    for(int i=0;i<=17;i++)
        if((dif>>i)&1)
            a=dp[i][a];
    if(a==b)
        return a;
    for(int i=17;i>=0;i--)
        if(dp[i][a]!=0&&dp[i][b]!=0)
            if(dp[i][a]!=dp[i][b])
            {
                a=dp[i][a];
                b=dp[i][b];
            }
    assert(par[a]==par[b]&&a!=b);
    return par[a];
}
void dfscalc(int nod)
{
    for(int q:muchii[nod])
    {
        int i=abs(q);
        if(i!=par[nod])
        {
            dfscalc(i);
            val[nod]+=val[i];
        }
    }
    if(val[nod])
    {
        int a=min(nod,par[nod]);
        int b=max(nod,par[nod]);
        for(int &i:muchii[a])
            if(i==b&&i>0)
                i=-i;
    }
    comp[nod]=what;
}
void dfsbuild(int nod)
{
    val[nod]=0;
    dp[0][nod]=par[nod];
    for(int i=1;i<=17;i++)
        dp[i][nod]=dp[i-1][dp[i-1][nod]];
    for(int q:muchii[nod])
    {
        int i=abs(q);
        if(i!=par[nod])
        {
            par[i]=nod;
            niv[i]=niv[nod]+1;
            dfsbuild(i);
        }
    }
}
void dsumerge(int a, int b)
{
    int c1=comp[a],c2=comp[b];
    if(lg[c1]<lg[c2])
    {
        swap(a,b);
        swap(c1,c2);
    }
    what=c1;
    dfscalc(myroot[c2]);
    par[b]=a;
    lg[c1]+=lg[c2];
    lg[c2]=0;
    niv[b]=niv[a]+1;
    muchii[a].push_back(b);
    muchii[b].push_back(a);
    dfsbuild(b);
}
int main()
{
    cin>>n>>m;
    muchii.resize(n+1);
    for(int i=1;i<=n;i++)
    {
        niv[i]=1;
        lg[i]=1;
        comp[i]=i;
        myroot[i]=i;
        par[i]=0;
        val[i]=0;
    }
    int cnt=0;
    for(int z=1;z<=m;z++)
    {
        int a,b;
        cin>>a>>b;
        if(comp[a]!=comp[b])
        {
            cnt++;
            dsumerge(a,b);
        }
        else
        {
            int lca=LCA(a,b);
            val[a]++;
            val[b]++;
            val[lca]-=2;
        }
    }
    assert(cnt<=n-1);
    for(int i=1;i<=n;i++)
        if(lg[i])
            dfscalc(myroot[i]);
    for(int i=1;i<=n;i++)
        for(int j:muchii[i])
            if(j>i&&j>0)
                cout<<i<<' '<<j<<'\n';
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 1096 KB Output is correct
2 Correct 8 ms 980 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 342 ms 852 KB Output is correct
2 Correct 316 ms 880 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 610 ms 1832 KB Output is correct
2 Correct 666 ms 1828 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 999 ms 4008 KB Output is correct
2 Correct 874 ms 4896 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1445 ms 10768 KB Output is correct
2 Correct 1207 ms 10760 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2312 ms 12340 KB Output is correct
2 Correct 2204 ms 12360 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3264 ms 15108 KB Output is correct
2 Correct 3062 ms 15188 KB Output is correct

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4024 ms 15196 KB Output is correct
2 Runtime error 3873 ms 17808 KB Memory limit exceeded
3 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4976 ms 14376 KB Output is correct
2 Runtime error 4493 ms 32112 KB Memory limit exceeded
3 Halted 0 ms 0 KB -