Submission #591627

# Submission time Handle Problem Language Result Execution time Memory
591627 2022-07-07T17:11:21 Z andrei_boaca Potemkin cycle (CEOI15_indcyc) C++14
70 / 100
941 ms 2036 KB
#include <bits/stdc++.h>
//#pragma GCC optimize("O3")
 
using namespace std;
mt19937 rng(time(NULL));
vector<int> muchii[1005];
auto S=chrono::steady_clock::now();
int n,m;
vector<int> v;
int use[1005];
int start=0;
void dfs(int nod)
{
    auto E=chrono::steady_clock::now();
    int x=chrono::duration_cast<chrono::milliseconds>(E - S).count();
    if(x>=950)
    {
        cout<<"no";
        exit(0);
    }
    use[nod]=v.size();
    bool good=1;
    bool ok=0;
    if(nod==4&&start==2)
    {
        /*for(int i:v)
            cout<<i<<' ';*/
        ok=1;
    }
    int pmax=0;
    for(int i:muchii[nod])
    {
        if(use[i])
        {
            if(i==v[v.size()-2])
                continue;
            if(i==start)
            {
                if(v.size()>=4);
                else
                    good=0;
            }
            else if(i!=v[v.size()-2])
                good=0;
            pmax=max(pmax,use[i]);
        }
    }
    if(v.size()-pmax+1>=4&&pmax!=0)
    {
        for(int i=pmax-1;i<v.size();i++)
            cout<<v[i]<<' ';
        exit(0);
    }
    if(good)
    {
        for(int i:muchii[nod])
            if(!use[i])
            {
                v.push_back(i);
                dfs(i);
                use[i]=0;
                v.pop_back();
            }
    }
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int a,b;
        cin>>a>>b;
        muchii[a].push_back(b);
        muchii[b].push_back(a);
    }
    for(int i=1;i<=n;i++)
        shuffle(muchii[i].begin(),muchii[i].end(),rng);
    vector<int> nodes;
    for(int i=1;i<=n;i++)
        nodes.push_back(i);
    shuffle(nodes.begin(),nodes.end(),rng);
    for(int i:nodes)
    {
        start=i;
        v.clear();
        v.push_back(i);
        for(int j=1;j<=n;j++)
            use[j]=0;
        dfs(i);
    }
    cout<<"no";
    return 0;
}

Compilation message

indcyc.cpp: In function 'void dfs(int)':
indcyc.cpp:50:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |         for(int i=pmax-1;i<v.size();i++)
      |                          ~^~~~~~~~~
indcyc.cpp:23:10: warning: variable 'ok' set but not used [-Wunused-but-set-variable]
   23 |     bool ok=0;
      |          ^~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 343 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 941 ms 388 KB Output is correct
2 Incorrect 939 ms 340 KB Expected integer, but "no" found
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 6 ms 340 KB Output is correct
2 Correct 920 ms 380 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 941 ms 1232 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 186 ms 740 KB Output is correct
2 Correct 933 ms 748 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 927 ms 2036 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -