답안 #581628

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
581628 2022-06-22T23:40:11 Z Lobo Jail (JOI22_jail) C++17
0 / 100
157 ms 239960 KB
#include<bits/stdc++.h>
using namespace std;

const long long inf = (long long) 1e18 + 10;
const int inf1 = (int) 1e9 + 10;
#define int long long
#define dbl long double
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()

const int maxn = 2e5+10;

int n, m, pp[maxn][25], pai[maxn], gr[50*maxn], h[maxn], s[maxn], t[maxn], up[maxn][25], dw[maxn][25];
vector<int> g[maxn], gts[50*maxn];
int cnt = 0;

void dfslca(int u, int ant) {
    pai[u] = ant;
    pp[u][0] = ant;
    for(int i = 1; i <= 20; i++) {
        pp[u][i] = pp[pp[u][i-1]][i-1];
    }

    //cria up
    up[u][0] = ++cnt;
    for(int i = 1; i <= 20; i++) {
        //liga dos de baixo pra cima
        up[u][i] = ++cnt;
        gts[up[u][i-1]].pb(up[u][i]);
        gts[up[pp[u][i-1]][i-1]].pb(up[u][i]);
    }

    //cria dw
    dw[u][0] = ++cnt;
    for(int i = 1; i <= 20; i++) {
        //liga do de cima para os debaixo
        dw[u][i] = ++cnt;
        gts[dw[u][i]].pb(dw[u][i-1]);
        gts[dw[u][i]].pb(dw[pp[u][i-1]][i-1]);
    }

    for(auto v : g[u]) if(v != ant) {
        h[v] = h[u]+1;
        dfslca(v,u);
    }
}

int lca(int u, int v) {
    if(h[u] < h[v]) swap(u,v);
    for(int i = 20; i >= 0; i--) {
        if(h[pp[u][i]] >= h[v]) {
            u = pp[u][i];
        }
    }
    if(u == v) return u;
    for(int i = 20; i >= 0; i--) {
        if(pp[u][i] != pp[v][i]) {
            u = pp[u][i];
            v = pp[v][i];
        }
    }
    return pp[u][0];
}

void solve() {
    cin >> n;
    cnt = 0;
    for(int i = 0; i <= n; i++) {
        g[i].clear();
    }
    for(int i = 0; i <= n*50; i++) {
        gts[i].clear();
        gr[i] = 0;
    }
    for(int i = 0; i < n-1; i++) {
        int u,v; cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
    cin >> m;
    cnt = m;
    h[0] = 0;
    h[1] = 1;
    dfslca(1,0);
    for(int i = 1; i <= m; i++) {
        cin >> s[i] >> t[i];
        if(s[i] == t[i]) return;
        //liga do i para s[i] e t[i]
        gts[i].pb(up[s[i]][0]);
        gts[dw[t[i]][0]].pb(i);
    }

    for(int i = 1; i <= m; i++) {
        int lc = lca(s[i],t[i]);
        // cout << s[i] << " "<< t[i] << " " << lc << endl;
        int v;
        //nao quero ligar do s[i] ate mim, entao faco o dw separado
        gts[i].pb(dw[s[i]][0]);
        v = pai[s[i]];
        //quero ir ate um antes do lc
        for(int j = 20; j >= 0; j--) {
            if(v != 0 && h[pp[v][j]] >= h[lc]) {
                gts[i].pb(dw[v][j]);
                gts[up[v][j]].pb(i);
                v = pp[v][j];
            }
        }
        
        gts[up[t[i]][0]].pb(i);
        v = pai[t[i]];
        //quero ir ate um antes do lc
        for(int j = 20; j >= 0; j--) {
            if(v != 0 && h[pp[v][j]] >= h[lc]) {
                gts[i].pb(dw[v][j]);
                gts[up[v][j]].pb(i);
                v = pp[v][j];
            }
        }

        if(lc != s[i] && lc != t[i]) {
            gts[i].pb(dw[lc][0]);
            gts[up[lc][0]].pb(i);
        }
    }

    for(int i = 1; i <= cnt; i++) {
        for(auto v : gts[i]) {
            gr[v]++;
        }
    }

    queue<int> q;
    for(int i = 1; i <= cnt; i++) {
        // cout << i << " " << gr[i] << endl;
        if(gr[i] == 0) q.push(i);
    }

    while(q.size()) {
        int u = q.front();
        q.pop();
        for(auto v : gts[u]) {
            if(--gr[v] == 0) q.push(v);
        }
    }

    string ans = "Yes";
    for(int i = 1; i <= m; i++) {
        if(gr[i] != 0) ans = "No";
    }
    cout << ans << endl;
}

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(0);

    freopen("in.in", "r", stdin);
    // freopen("out.out", "w", stdout);
    int tt = 1;
    cin >> tt;
    while(tt--) {
        solve();
    }

}

Compilation message

jail.cpp: In function 'int32_t main()':
jail.cpp:160:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  160 |     freopen("in.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 157 ms 239892 KB Output is correct
2 Incorrect 119 ms 239920 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 131 ms 239900 KB Output is correct
2 Incorrect 125 ms 239884 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 131 ms 239900 KB Output is correct
2 Incorrect 125 ms 239884 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 131 ms 239900 KB Output is correct
2 Incorrect 125 ms 239884 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 131 ms 239900 KB Output is correct
2 Incorrect 125 ms 239884 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 135 ms 239960 KB Output is correct
2 Incorrect 130 ms 239888 KB Output isn't correct
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 157 ms 239892 KB Output is correct
2 Incorrect 119 ms 239920 KB Output isn't correct
3 Halted 0 ms 0 KB -