Submission #854320

#	Time	Username	Problem	Language	Result	Execution time	Memory
854320		mychecksedad	The short shank; Redemption (BOI21_prison)	C++17	100 / 100	1884 ms	500560 KiB

prison

/* Author : Mychecksdead  */
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
const int N = 9e6+100, M = 2e6+10, K = 22;


int n, d, et, a[M], P[M], ans = 0, T[N], lazy[N];
vector<int> V[N];
vector<bool> removed(M);
void build(int l, int r, int k){
  if(l == r){
    T[k] = lazy[k] = 0;
    return;
  }
  int m = l+r>>1;
  build(l, m, k<<1);
  build(m+1, r, k<<1|1);
  T[k] = lazy[k] = 0;
}
void push(int k){
  if(lazy[k] != 0){
    lazy[k<<1] += lazy[k];
    lazy[k<<1|1] += lazy[k];
    T[k<<1] += lazy[k];
    T[k<<1|1] += lazy[k];
    lazy[k] = 0;
  }
}
void update(int l, int r, int ql, int qr, int k, int val, int pushed){
  if(ql > r || l > qr) return;
  if(ql <= l && r <= qr){
    T[k] += val;
    lazy[k] += val;
    if(pushed != -1) V[k].pb(pushed);
    return;
  }
  push(k);
  int m = l+r>>1;
  update(l, m, ql, qr, k<<1, val, pushed);
  update(m+1, r, ql, qr, k<<1|1, val, pushed);
  T[k] = max(T[k<<1], T[k<<1|1]);
}
pair<int, int> get_max(int l, int r, int k){
  if(l == r) return {l, T[k]};
  int m = l + r >> 1;
  push(k);
  if(T[k<<1] > T[k<<1|1])
    return get_max(l, m, k<<1);
  return get_max(m + 1, r, k<<1|1);
}

void rem(int l, int r, int p, int k){
  if(l > p || r < p) return;
  if(l == r){
    for(auto id: V[k]) if(!removed[id]){
      removed[id] = 1;
      update(1, n - 1, P[id], id - 1, 1, -1, -1);
    }
    V[k].clear();
    return;
  }
  for(auto id: V[k]) if(!removed[id]){
    removed[id] = 1;
    update(1, n - 1, P[id], id - 1, 1, -1, -1);
  }
  V[k].clear();
  int m = l + r >> 1;
  push(k);
  rem(l, m, p, k<<1);
  rem(m+1, r, p, k<<1|1);
}

void solve(){
  cin >> n >> d >> et;
  ans = n;
  for(int i = 1; i <= n; ++i){
    cin >> a[i];
    a[i] -= i;
  }
  deque<int> q;
  for(int i = 1; i <= n; ++i){
    if(a[i] + i <= et){
      P[i] = i;
      q.pb(i);
    }else{
      while(!q.empty() && a[q.back()] + i > et){
        q.pop_back();
      }
      if(q.empty()) P[i] = -1, --ans;
      else P[i] = q.back();
    }
  }
  build(1, n - 1, 1);
  for(int i = 1; i <= n; ++i){
    if(P[i] != i && P[i] != -1){
      int l = P[i], r = i - 1;
      update(1, n - 1, l, r, 1, 1, i);
    }
  }

  while(d--){
    pair<int, int> pos = get_max(1, n - 1, 1);
    ans -= pos.second;
    rem(1, n - 1, pos.first, 1);
  }


  cout << ans;
}



int main(){
  cin.tie(0); ios::sync_with_stdio(0);
  int tt = 1, aa;
  // freopen("in.txt", "r", stdin);
  // freopen("out.txt", "w", stdout);
  while(tt--){
    solve();
  }
  cerr<<"time taken : "<<(float)clock()/CLOCKS_PER_SEC<<" seconds\n";
  return 0;
} 

Compilation message (stderr)

prison.cpp: In function 'void build(int, int, int)':
prison.cpp:21:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   21 |   int m = l+r>>1;
      |           ~^~
prison.cpp: In function 'void update(int, int, int, int, int, int, int)':
prison.cpp:44:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   44 |   int m = l+r>>1;
      |           ~^~
prison.cpp: In function 'std::pair<int, int> get_max(int, int, int)':
prison.cpp:51:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   51 |   int m = l + r >> 1;
      |           ~~^~~
prison.cpp: In function 'void rem(int, int, int, int)':
prison.cpp:73:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   73 |   int m = l + r >> 1;
      |           ~~^~~
prison.cpp: In function 'int main()':
prison.cpp:121:15: warning: unused variable 'aa' [-Wunused-variable]
  121 |   int tt = 1, aa;
      |               ^~

• Subtask 1: 15 / 15
• Subtask 2: 10 / 10
• Subtask 3: 20 / 20
• Subtask 4: 10 / 10
• Subtask 5: 25 / 25
• Subtask 6: 20 / 20