Submission #694021

#	Time	Username	Problem	Language	Result	Execution time	Memory
694021		4EVER	Jail (JOI22_jail)	C++11	0 / 100	3 ms	5076 KiB

jail

#include <bits/stdc++.h>

using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

#define PB push_back
#define ALL(i_) i_.begin(), i_.end()
#define LOG2(x_) (31 - __builtin_clz(x_))
#define getBit(x_, i_) ((x_ >> i_) & (ll) 1)
#define rd(l_, r_) (l_ + rng() % (r_ - l_ + 1))
#define FOR(i_, a_, b_)  for(int i_ = (int) (a_); i_ <= (int) (b_); ++i_)
#define FORD(i_, a_, b_) for(int i_ = (int) (a_); i_ >= (int) (b_); --i_)

void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef DEBUG
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

typedef long long ll;
typedef long double ld;

template<class X, class Y> bool minimize(X &x, const Y &y){
    X eps = 1e-9;
    if (x > y + eps) {
        x = y;
        return 1;
    }
    return 0;
}

template<class X, class Y> bool maximize(X &x, const Y &y) {
    X eps = 1e-9;
    if (x + eps < y) {
        x = y;
        return 1;
    }
    return 0;
}

template<class T> T Abs(const T &x) { return (x < 0 ? -x : x); }
template<class T> using heap_min = priority_queue<T, vector<T>, greater<T>>;
template<class T> using heap_max = priority_queue<T>;

// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;
// typedef tree<pair<int, int>, null_type, less<pair<int, int>>, rb_tree_tag, tree_order_statistics_node_update> OST;

const int mod = (int) 1e9 + 7; // 998244353
const int oo = (int) 1e9 + 99;
const array<int, 2> dxy8[] = { {-1, 0}, {1, 0}, {0, 1}, {0, -1}, {1, -1}, {1, 1}, {-1, 1}, {-1, -1} };
const array<int, 2> dxy4[] = { {-1, 0}, {1, 0}, {0, 1}, {0, -1} };

const int maxn = (int) 1e5 + 11;
const int LOG = (int) LOG2(maxn) + 3;

void File(){
    #define TASK "JAIL"
    if(fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }
}

int n, m;
vector<int> adj[maxn];
int s[maxn], t[maxn];

void ReadInput(){
    cin >> n;
    FOR(i, 1, n) adj[i].clear();
    FOR(i, 1, n - 1){
        int u, v; cin >> u >> v;
        adj[u].PB(v);
        adj[v].PB(u);
    }
    cin >> m;
    FOR(i, 1, m) cin >> s[i] >> t[i];
}

int cnt;
int depth[maxn], tin[maxn], tout[maxn];
int spt[LOG + 3][maxn];

void DFS(int u = 1, int par = -1){
    tin[u] = ++cnt;
    for(int v : adj[u]) if(v != par){
        depth[v] = depth[u] + 1;
        spt[0][v] = u;
        FOR(i, 1, LOG) spt[i][v] = spt[i - 1][spt[i - 1][v]];
        DFS(v, u);
    }
    tout[u] = cnt;
}

int LCA(int u, int v){
    if(depth[u] < depth[v]) swap(u, v);
    int k = depth[u] - depth[v];
    FORD(i, LOG, 0) if(getBit(k, i)) u = spt[i][u];
    if(u == v) return u;
    FORD(i, LOG, 0) if(spt[i][u] != spt[i][v]){
        u = spt[i][u];
        v = spt[i][v];
    }
    return spt[0][u];
}

bool Anc(int v, int u){
    return (tin[u] <= tin[v] && tout[v] <= tout[u]);
}

bool Inpath(int x, int u, int v){
    if(!Anc(x, LCA(u, v))) return 0;
    return Anc(u, x) || Anc(v, x);
}

vector<int> ke[maxn];
int deg[maxn];

void Solve(){
    DFS();
    FOR(i, 1, m){
        deg[i] = 0;
        ke[i].clear();
    }
    FOR(i, 1, m){
        FOR(j, 1, m) if(i != j){
            if(Inpath(s[j], s[i], t[i])){
                ke[j].PB(i);
                ++deg[i];
            }
            if(Inpath(t[j], s[i], t[i])){
                ke[i].PB(j);
                ++deg[j];
            }
        }
    }
    queue<int> que;
    FOR(i, 1, m) if(!deg[i]) que.push(i);
    while(!que.empty()){
        int u = que.front(); que.pop();
        for(int v : ke[u]){
            --deg[v];
            if(!deg[v]) que.push(v);
        }
    }
    int res = 1;
    FOR(i, 1, m) res &= (deg[i] == 0);
    cout << (res ? "YES\n" : "NO\n");
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    File();
    int ntest; cin >> ntest;
    while(ntest--){
        ReadInput();
        Solve();
    }
    cerr << "\nTime elapsed: " << 1000.0 * clock() / CLOCKS_PER_SEC << " ms.\n";
    return 0;
}

Compilation message (stderr)

jail.cpp: In function 'void File()':
jail.cpp:82:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   82 |         freopen(TASK".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
jail.cpp:83:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |         freopen(TASK".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 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