Submission #997252

#	Time	Username	Problem	Language	Result	Execution time	Memory
997252		vladilius	Jail (JOI22_jail)	C++17	5 / 100	108 ms	46420 KiB

jail

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second
#define ins insert

struct FT{
    vector<int> bit;
    int n;
    FT(int ns){
        n = ns;
        bit.resize(n + 1);
    }
    void add(int v, int k){
        while (v <= n){
            bit[v] += k;
            v |= (v + 1);
        }
    }
    void upd(int l, int r, int x){
        add(l, x);
        add(r + 1, -x);
    }
    int get(int v){
        int out = 0;
        while (v > 0){
            out += bit[v];
            v = (v & (v + 1)) - 1;
        }
        return out;
    }
};

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int tt; cin>>tt;
    while (tt--){
        int n; cin>>n;
        vector<int> g[n + 1];
        for (int i = 1; i < n; i++){
            int a, b; cin>>a>>b;
            g[a].pb(b);
            g[b].pb(a);
        }
        
        const int lg = log2(n);
        vector<vector<int>> pw(n + 1, vector<int>(lg + 1));
        vector<int> tin(n + 1), tout(n + 1);
        int timer = 0;
        function<void(int, int)> fill = [&](int v, int pr){
            tin[v] = ++timer;
            pw[v][0] = pr;
            for (int i = 1; i <= lg; i++){
                pw[v][i] = pw[pw[v][i - 1]][i - 1];
            }
            for (int i: g[v]){
                if (i == pr) continue;
                fill(i, v);
            }
            tout[v] = timer;
        };
        fill(1, 1);
        
        auto check = [&](int x, int y){
            return (tin[x] <= tin[y] && tout[x] >= tout[y]);
        };
        
        int m; cin>>m;
        vector<int> s(m + 1), t(m + 1);
        for (int i = 1; i <= m; i++){
            cin>>s[i]>>t[i];
        }
        
        auto lca = [&](int x, int y){
            if (check(x, y)) return x;
            if (check(y, x)) return y;
            for (int i = lg; i >= 0; i--){
                if (!check(pw[x][i], y)){
                    x = pw[x][i];
                }
            }
            return pw[x][0];
        };
        
        vector<int> p1(n + 1), p2(n + 1);
        for (int i = 1; i <= n; i++){
            p1[i] = p2[i] = i;
        }
        vector<int> w1(n + 1), w2(n + 1);
        for (int i = 1; i <= m; i++){
            w1[s[i]] = w2[t[i]] = i;
        }
        
        pw[1][0] = 0;
        function<int(int)> move1 = [&](int v){
            if (w1[v] || !v) return v;
            if (p1[v] == v){
                p1[v] = pw[v][0];
            }
            return p1[v] = move1(p1[v]);
        };
        
        function<int(int)> move2 = [&](int v){
            if (w2[v] || !v) return v;
            if (p2[v] == v){
                p2[v] = pw[v][0];
            }
            return p2[v] = move2(p2[v]);
        };
        
        vector<int> f[m + 1];
        function<void(int)> dfs1 = [&](int v){
            w1[s[v]] = 0;
            int l = lca(s[v], t[v]), x;
            while (check(l, x = move1(s[v]))){
                f[v].pb(w1[x]);
                dfs1(w1[x]);
            }
            while (check(l, x = move1(t[v]))){
                f[v].pb(w1[x]);
                dfs1(w1[x]);
            }
        };
        
        function<void(int)> dfs2 = [&](int v){
            w2[t[v]] = 0;
            int l = lca(s[v], t[v]), x;
            while (check(l, x = move2(s[v]))){
                f[w2[x]].pb(v);
                dfs2(w2[x]);
            }
            while (check(l, x = move2(t[v]))){
                f[w2[x]].pb(v);
                dfs2(w2[x]);
            }
        };
        
        for (int i = 1; i <= m; i++){
            if (w1[s[i]]){
                dfs1(i);
            }
        }
        for (int i = 1; i <= m; i++){
            if (w2[t[i]]){
                dfs2(i);
            }
        }
        
        vector<bool> used(m + 1), seen(m + 1);
        vector<int> order;
        bool out = 1;
        function<void(int)> dfs = [&](int v){
            if (!out) return;
            used[v] = seen[v] = 1;
            for (int i: f[v]){
                if (used[i]){
                    if (seen[i]){
                        out = 0;
                        return;
                    }
                    continue;
                }
                dfs(i);
            }
            order.pb(v);
            seen[v] = 0;
        };
        for (int i = 1; i <= m; i++){
            if (!used[i]){
                dfs(i);
            }
        }
        
        if (!out){
            cout<<"No"<<"\n";
            continue;
        }
        
        vector<int> a(n + 1);
        FT T(n);
        auto upd = [&](int v, int k){
            a[v] += k;
            T.upd(tin[v], tout[v], k);
        };
        
        for (int i = 1; i <= m; i++){
            upd(s[i], 1);
        }
        
        auto get = [&](int x, int y){
            int l = lca(x, y);
            return T.get(tin[x]) + T.get(tin[y]) - 2 * T.get(tin[l]) + a[l];
        };
        
        for (int i: order){
            if (get(s[i], t[i]) > 1){
                out = 0;
                break;
            }
            upd(s[i], -1);
            upd(t[i], 1);
        }
        
        cout<<((out) ? "Yes" : "No")<<"\n";
    }
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 5
• Subtask 3: 0 / 16
• Subtask 4: 0 / 28
• Subtask 5: 0 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23