Submission #876152

# Submission time Handle Problem Language Result Execution time Memory
876152 2023-11-21T10:22:55 Z Ice_man Jail (JOI22_jail) C++17
0 / 100
13 ms 860 KB
#include <iostream>
#include <vector>
#include <cstring>
#include <stack>

#define maxn 1005
#define maxlog 20
#define pb(x) push_back(x)

#pragma GCC optimize("O3" , "Ofast" , "unroll-loops")
#pragma GCC target(avx2)

using namespace std;

int n , m ,  q;
vector <int> v[maxn];
int start[maxn] , _final[maxn];
vector <int> new_tree[maxn];
int bin_lift[maxn][maxlog];
int pom1[maxn];
int pom2[maxn];

void read()
{
    cin >> n;

    for(int i = 1; i <= n; i++)
    {
        for(int j = 0; j < maxlog; j++) bin_lift[i][j] = 0;
    }

    for(int i = 1; i <= n; i++)
    {
        v[i].clear();
        new_tree[i].clear();
    }

    int from , to;
    for(int i = 1; i <= (n - 1); i++)
    {
        cin >> from >> to;

        v[from].pb(to);
        v[to].pb(from);
    }

    cin >> m;

    for(int i = 1; i <= m; i++)
    {
        pom1[i] = 0;
        pom2[i] = 0;
    }

    for(int i = 1; i <= m; i++) cin >> start[i] >> _final[i];
}

///int bin_lift[maxn][maxlog];
int depth[maxn];

void calc_bin(int node , int parent)
{
    for(int nb : v[node])
    {
        if(nb != parent)
        {
            bin_lift[nb][0] = node;
            for(int i = 1; i < maxlog; i++) bin_lift[nb][i] = bin_lift[bin_lift[nb][i - 1]][i - 1];

            depth[nb] = depth[node] + 1;
            calc_bin(nb , node);
        }
    }

}


int get_lca(int a , int b)
{
    if(depth[a] < depth[b]) swap(a , b);

    ///cout << a << "-" << b << endl;

    int levels = depth[a] - depth[b];
    ///cout << "** " << levels << endl;;
    for(int i = maxlog - 1; i >= 0; i--)
    {
        if(levels >> i & 1)
        {
            ///cout  << ">< "<< (1 << i) << endl;
            a = bin_lift[a][i];
            ///levels -= (1 << i);
            ///cout << (1 << i) << endl;
        }
    }

    ///cout << a << "-" << b << endl;
    if(a == b) return a;

    for(int i = maxlog - 1; i >= 1; i--)
    {
        if(!bin_lift[a][i]) continue;
        if(!bin_lift[b][i]) continue;

        if(bin_lift[a][i] != bin_lift[b][i])
        {
            a = bin_lift[a][i];
            b = bin_lift[b][i];
        }

    }

    return bin_lift[a][0];

}

bool check(int a , int b , int c)
{
    int lca = get_lca(a , b);
    ///int pom = get_lca(lca , c);

    if(get_lca(lca , c) == lca && get_lca(c , a) == c) return true;
    if(get_lca(lca , c) == lca && get_lca(c , b) == c) return true;

    return false;

}

//vector <int> new_tree[maxn];

void solve()
{

    calc_bin(1 , 0);

    for(int a = 1; a <= m; a++)
    {
        for(int b = 1; b <= m; b++)
        {
            if(a != b)
            {
                int lca1 = get_lca(start[a] , _final[a]);

                if(check(start[a] , _final[a] , start[b]) == true) new_tree[b].pb(a);
                else if(check(start[a] , _final[a] , _final[b]) == true) new_tree[a].pb(b);

                ///cout << check(start[a] , _final[a] , start[b]) << " " <<  check(start[a] , _final[a] , _final[b]) << endl;

            }
        }
    }

     /**for(int i = 1; i <= n; i++)
    {
        cout << i << ": ";
        for(int nb : new_tree[i]) cout << nb << " ";
        cout << endl;
    }*/

}

stack <int> s;
///int pom1[maxn] , pom2[maxn];
int _time = 0;
int br = 0;

void count_ssc(int node , int parent)
{
    s.push(node);
    _time++;

    pom1[node] = _time;
    pom2[node] = _time;

    for(int nb : new_tree[node])
    {
        if(pom2[nb] != -1)
        {
            if(pom2[nb])
            {
                pom1[node] = min(pom1[node] , pom1[nb]);
            }
            else
            {
                count_ssc(nb , node);
                pom1[node] = min(pom1[node] , pom1[nb]);
            }
        }
    }

    if(pom1[node] == pom2[node])
    {
        br++;
        while(!s.empty() && s.top() != node)
        {
            pom2[s.top()] = -1;
            s.pop();
        }
        pom2[node] = -1;
        s.pop();
    }


}

void combine()
{
    cin >> q;
    while(q--)
    {
        br = 0;
        _time = 0;

        read();
        solve();

        /**for(int i = 1; i <= n; i++)
        {
            cout << i << ": ";
            for(int power = 0; power < maxlog; power++)
            {
                cout << bin_lift[i][power] << " ";
            }
            cout << endl;
        }*/

        ///cout << "-> " << get_lca(1 , 5) << endl;

        for(int i = 1; i <= m; i++) if(!pom2[i]) count_ssc(i , -1);

        if(br == m) cout << "Yes" << endl;
        else cout << "No" << endl;

    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    combine();

    return 0;

}

Compilation message

jail.cpp:11:20: warning: '#pragma GCC option' is not a string [-Wpragmas]
   11 | #pragma GCC target(avx2)
      |                    ^~~~
jail.cpp: In function 'void solve()':
jail.cpp:142:21: warning: unused variable 'lca1' [-Wunused-variable]
  142 |                 int lca1 = get_lca(start[a] , _final[a]);
      |                     ^~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Incorrect 9 ms 860 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 1 ms 344 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 1 ms 344 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 1 ms 344 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Incorrect 1 ms 344 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Incorrect 13 ms 604 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Incorrect 9 ms 860 KB Output isn't correct
5 Halted 0 ms 0 KB -