Submission #47764

#	Time	Username	Problem	Language	Result	Execution time	Memory
47764		Just_Solve_The_Problem	Bitaro’s Party (JOI18_bitaro)	C++11	0 / 100	10 ms	8184 KiB

bitaro

#include <bits/stdc++.h>

using namespace std;

#define pb push_back
#define eb emplace_back
#define ll long long
#define pii pair < int, int >
#define fr first
#define sc second
#define mk make_pair
#define sz(s) (int)s.size()
#define all(s) s.begin(), s.end()
#define ok puts("ok");
#define whatis(x) cerr << #x << " = " << x << endl;
#define pause system("pause");
#define random (rand() ^ (rand() << 15))

const int N = (int)1e5 + 7;
const int inf = (int)1e9 + 7;

struct T {
  vector < int > tree;
  int sz;
  T() {
    sz = 0;
    tree.clear();
  }
  T(int _sz) {
    sz = _sz;
    tree.resize(4 * sz, 0);
  }
  void upd(int pos, int val, int v, int tl, int tr) {
    if (tl == tr) {
      tree[v] = val;
      return ;
    }
    int mid = (tl + tr) >> 1;
    if (pos <= mid) {
      upd(pos, val, v + v, tl, mid);
    } else {
      upd(pos, val, v + v + 1, mid + 1, tr);
    }
    tree[v] = tree[v + v] + tree[v + v + 1];
  }
  int get(int l, int r, int v, int tl, int tr) {
    if (tl == tr) return tl;
    if (tree[1] == 0) return -1;
    int mid = (tl + tr) >> 1;
    if (tree[v + v]) {
      return get(l, r, v + v, tl, mid);
    } else {
      return get(l, r, v + v + 1, mid + 1, tr);
    }
  }
};

T seg[N];
int n, m, q, t, y, newchain;
vector < int > gr[N];
vector < int > revgr[N];
int used[N], h[N], deg[2][N], u[N], uh[N];
int chain[N], chainpos[N], chainsz[N], pr[N], head[N], was[N];

void dfs(int v) {
  u[v] = 1;
  for (int to : gr[v]) {
    if (!u[to])
      dfs(to);
    h[v] = max(h[to] + 1, h[v]);
  }
}

void buildhld(int v, int curchain, int p) {
  int siz = -1;
  int bigchild = -1;
  uh[v] = 1;
  chain[v] = curchain;
  pr[v] = p;
  chainpos[v] = ++chainsz[curchain];
  if (chainsz[curchain] == 1) {
    head[curchain] = v;
  }
  for (int to : gr[v]) {
    if (uh[to]) continue;
    if (h[to] > siz) {
      siz = h[to];
      bigchild = to;
    }
  }
  if (bigchild != -1) {
    buildhld(bigchild, curchain, v);
  }
  for (int to : gr[v]) {
    if (uh[to]) continue;
    buildhld(to, ++newchain, v);
  }
}

int getans(int x) {
  int ret = -1;
  int v = x;
  int sum = 0;
  int ans = 0;
  while (v) {
    int chai = chain[v];
    int gg = seg[chai].get(1, chainpos[v], 1, 1, chainsz[chai]);
    if (gg != -1 && gg <= chainpos[v]) {
//      whatis(gg);
      ans = sum + (chainpos[v] - gg + 1);
      ret = gg;
    }
    sum += chainpos[v];
    v = pr[head[chai]];
  }
  if (ret == -1) return -1;
  return ans - 1;
}

main() {
  scanf("%d %d %d", &n, &m, &q);
  for (int i = 1; i <= m; i++) {
    int u, v;
    scanf("%d %d", &u, &v);
    gr[u].pb(v);
    deg[0][v]++;
    deg[1][u]++;
    revgr[v].pb(u);
  }
  for (int i = 1; i <= n; i++) {
    if (!deg[0][i]) {
      dfs(i);
      buildhld(i, ++newchain, 0);
    }
  }
  for (int i = 1; i <= n; i++) {
    if (!was[chain[i]]) {
      seg[chain[i]] = T(chainsz[chain[i]]);
    }
    seg[chain[i]].upd(chainpos[i], 1, 1, 1, chainsz[chain[i]]);
    was[chain[i]] = 1;
  }
  while (q--) {
    scanf("%d %d", &t, &y);
    vector < int > v;
    for (int i = 1; i <= y; i++) {
      int x;
      scanf("%d", &x);
      v.pb(x);
      seg[chain[x]].upd(chainpos[x], 0, 1, 1, chainsz[chain[x]]);
    }
    // solve
    int ans = getans(t);
    printf("%d\n", ans);
    // answer query
    for (int to : v) {
      seg[chain[to]].upd(chainpos[to], 1, 1, 1, chainsz[chain[to]]);
    }
  }
}

Compilation message (stderr)

bitaro.cpp:120:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
bitaro.cpp: In function 'int main()':
bitaro.cpp:121:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d", &n, &m, &q);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:124:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &u, &v);
     ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:144:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &t, &y);
     ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:148:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
       scanf("%d", &x);
       ~~~~~^~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86