제출 #632032

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
632032		Soul234	동기화 (JOI13_synchronization)	C++14	100 / 100	274 ms	25408 KiB

synchronization

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

void DBG() { cerr << "]\n"; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << h; if(sizeof...(t)) cerr << ", ";
    DBG(t...);
}
#ifdef LOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif // LOCAL

#define FOR(i,a,b) for(int i = (a) ; i<(b) ; i++)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for(int i = (b)-1 ; i>=(a) ; i--)
#define R0F(i,a) ROF(i,0,a)
#define each(e,a) for(auto &e : (a))
#define sz(v) (int)(v).size()
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
#define tcT template<class T
#define nl "\n"

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using str = string;
tcT> using V = vector<T>;
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;

void setIO(string NAME = "") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(NAME)) {
        freopen((NAME + ".inp").c_str(),"r",stdin);
        freopen((NAME + ".out").c_str(),"w",stdout);
    }
}

tcT> bool ckmin(T&a, const T&b) {
    return b < a ? a=b,1 : 0; }
tcT> bool ckmax(T&a, const T&b) {
    return b > a ? a=b,1 : 0; }

const int MOD = 1e9 + 7;

struct BIT {
    int N;
    vi bit;
    void init(int _N) {
        N = _N;
        bit.assign(N + 7, 0);
    }
    void updInc(int p, int val) {
        for(; p<=N; p += p&-p) bit[p] += val;
    }
    int query(int p) {
        int res = 0;
        for(; p>0; p -= p&-p) res += bit[p];
        return res;
    }
} fen;

const int MX = 1e5+5, LG = 18;
int N, M, Q, tt, tin[MX], tout[MX], par[MX][LG], isact[MX], cnt[MX], lst[MX];
vi adj[MX];
pi eds[MX];

void dfs(int u, int p) {
    tin[u] = ++tt;
    cnt[u] = 1;
    each(v, adj[u]) if(v != p) {
        par[v][0] = u;
        dfs(v, u);
    }
    tout[u] = tt;
}

int get_anc(int u) {
    int res = u;
    R0F(i, LG) if(fen.query(tin[par[res][i]]) == fen.query(tin[u]))
        res = par[res][i];
    return res;
}

void solve() {
    cin >> N >> M >> Q;
    fen.init(N+5);
    F0R(i, N-1) {
        int u,v;
        cin >> u >> v;
        adj[u].pb(v);
        adj[v].pb(u);
        eds[i+1] = {u, v};
    }
    par[1][0] = 1;
    dfs(1, -1);
    FOR(j,1,LG) FOR(i,1,N+1) par[i][j] = par[par[i][j-1]][j-1];
    FOR(i,2,N+1) {
        fen.updInc(tin[i], 1);
        fen.updInc(tout[i]+1, -1);
    }
    F0R(i, M) {
        int ind;
        cin >> ind;
        int u = eds[ind].first, v = eds[ind].second;
        if(par[u][0] == v) swap(u, v);
        if(isact[v]) {
            int rt = get_anc(u);
            cnt[v] = lst[v] = cnt[rt];
            fen.updInc(tin[v], 1);
            fen.updInc(tout[v]+1, -1);
        }
        else {
            int rt = get_anc(u);
            cnt[rt] = cnt[rt] + cnt[v] - lst[v];
            fen.updInc(tin[v], -1);
            fen.updInc(tout[v]+1, 1);
        }
        isact[v] ^= 1;
    }
    while(Q-- > 0) {
        int v; cin >> v;
        v = get_anc(v);
        cout << cnt[v] << nl;
    }
}

int main() {
    setIO();

    int t=1;
    //cin>>t;
    while(t-->0) {
        solve();
    }

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

synchronization.cpp: In function 'void setIO(std::string)':
synchronization.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen((NAME + ".inp").c_str(),"r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
synchronization.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen((NAME + ".out").c_str(),"w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40