Submission #580280

#	Time	Username	Problem	Language	Result	Execution time	Memory
580280		balbit	Jail (JOI22_jail)	C++14	72 / 100	5103 ms	1021760 KiB

jail

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pii pair<ll, ll>
#define f first
#define s second

#define MX(a,b) a = max(a,b)
#define MN(a,b) a = min(a,b)

#define SZ(x) (int)(x).size()
#define ALL(x) (x).begin(), (x).end()
#define pb push_back

#define FOR(i,a,b) for (int i = a; i<b; ++i)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n+1)

#ifdef BALBIT
#define bug(...) cerr<<"#"<<__LINE__<<": "<<#__VA_ARGS__<<"- ", _do(__VA_ARGS__)
template<typename T> void _do( T && x) {cerr<<x<<endl;}
template<typename T, typename ...S> void _do( T && x, S && ...y) {cerr<<x<<", "; _do(y...);}
#else
#define bug(...)
#define endl '\n'
#endif // BALBIT

const int maxn = 2e5+5;


vector<int> tree[maxn];
int dep[maxn];
int fa[18][maxn];
int nxt[maxn];
int st[maxn], en[maxn]; // starting or ending???

void dfs(int v, int p) {
    if (st[v]!=-1 || en[v]!=-1) {
        nxt[v] = v;

    }else{
        nxt[v] = p == -1? -1 : nxt[p];
    }
    bug(v, nxt[v]);
    for (int u : tree[v]) {
        if (u == p) continue;
        dep[u] = dep[v] + 1;
        fa[0][u] = v;
        dfs(u,v);
    }
}

int snode[maxn], enode[maxn];
void CLR(int n){
    REP(i,n) {
        tree[i].clear(); dep[i] = 0;
        st[i] = en[i] = -1;
        nxt[i] = -1;
    }
}

int lca(int a, int b) {
    if (dep[a] < dep[b]) swap(a,b);
    int need = dep[a] - dep[b];
    REP(k, 18) if (need & (1<<k)) a = fa[k][a];
    assert(dep[a] == dep[b]);
    for (int j = 17; j>=0; --j) {
        if (fa[j][a] != fa[j][b]) {
            a = fa[j][a]; b = fa[j][b];
        }
    }
    if (a != b) return fa[0][a];
    return a;
}

vector<int> g[maxn];
int indeg[maxn];

signed main(){
    ios::sync_with_stdio(0), cin.tie(0);
    bug(1,2);

    int T; cin>>T;
    while (T--) {
        int n; cin>>n;
        CLR(n);

        REP(i,n-1) {
            int a,b; cin>>a>>b; --a; --b;
            tree[a].pb(b); tree[b].pb(a);
        }


        int q; cin>>q;
        REP(i,q) {
            cin>>snode[i]>>enode[i]; --snode[i]; --enode[i];
            st[snode[i]] = i; en[enode[i]] = i;
        }

        dfs(0,-1);

        REP1(j, 18-1) {
            REP(i,n) {
                fa[j][i] = fa[j-1][fa[j-1][i]];
            }
        }

        REP(i,q) g[i].clear();

        REP(i,q) {
            int a = snode[i], b = enode[i];
            int c = lca(a,b);
//            bool yo = 0;

            for (int v : {a,b}) {
                v = nxt[v];
                while (v != -1 && dep[v] >= dep[c]) {
                    if (~st[v] && st[v] != i) {
                        g[i].pb(st[v]);
                        bug(i, st[v]);
                    }
                    if (~en[v] && en[v] != i) {
                        g[en[v]].pb(i);
                        bug(en[v], i);
                    }
                    if (v == 0) break;
                    v = nxt[fa[0][v]];
                    bug(v, fa[0][v], nxt[fa[0][v]]);
                }
            }

        }

        REP(i,q) {
            indeg[i] = 0;
        }
        REP(i,q) {
            for (int u : g[i]) {
                ++indeg[u];
            }
        }
        queue<int> qq;
        REP(i,q) {
            if (indeg[i] == 0) {
                qq.push(i);
            }
        }
        int done = 0;
        while (!qq.empty() ){
            int v = qq.front(); qq.pop();
            ++done;
            for (int u : g[v]) {
                if (--indeg[u] == 0) {
                    qq.push(u);
                }
            }
        }

        bug(done);
        cout<<(done==q?"Yes":"No")<<endl;

    }


}

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