Submission #742459

#	Time	Username	Problem	Language	Result	Execution time	Memory
742459		penguin133	The short shank; Redemption (BOI21_prison)	C++17	10 / 100	274 ms	79036 KiB

prison

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

#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

int n, k, t, A[500005];
int P[500005], S[500005];
/*
int memo[501][501][501], mn[501][501];
int dp(int x, int y, int prv){
	if(x == n + 1)return 0;
	if(memo[x][y][prv] != -1)return memo[x][y][prv];
	int ans = dp(x + 1, y , prv);
	if(y)ans = min(ans, dp(x + 1, y - 1, x + 1));
	return memo[x][y][prv] = ans + (mn[prv][x] + x <= t);
}*/

struct node{
	int s, e, m, val, lazy;
	node *l, *r;
	node(int _s, int _e){
		s = _s, e = _e, m = (s + e) >> 1;
		if(s != e)l = new node(s, m), r = new node(m+1, e);
		val = lazy = 0;
	}
	void prop(){
		if(lazy){
			val = lazy;
			if(s != e)l->lazy = lazy, r->lazy = lazy;
			lazy =0 ;
		}
	}
	
	void upd(int a, int b, int c){
		prop();
		if(a == s && b == e)lazy = c;
		else{
			if(b <= m)l->upd(a, b, c);
			else if(a > m)r->upd(a, b, c);
			else l->upd(a, m, c), r->upd(m+1, b, c);
			l->prop(), r->prop();
			
		}
	}
	
	int qry(int x){
		prop();
		if(s == e)return val;
		else if(x <= m)return l->qry(x);
		else return r->qry(x);
	}
}*root;

void solve(){
	cin >> n >> k >> t;
	for(int i=1;i<=n;i++)cin >> A[i], A[i] -= i;
	/*
	for(int i=1;i<=n;i++){
		mn[i][i] = A[i];
		for(int j=i+1;j<=n;j++)mn[i][j] = min(mn[i][j-1], A[j]);
	}
	*/
	int cur = 1e18;
	for(int i=1;i<=n;i++){
		cur = min(cur, A[i]);
		if(cur + i <= t)P[i]++;
		P[i] += P[i-1];
	}
	vector <int> v;
	root = new node(1, n);
	for(int i=1;i<=n;i++){
		int rgt = t - A[i];
		rgt = min(rgt, n);
		if(rgt < i)continue;
		root->upd(i, rgt, i);
	}
	for(int i=1;i<=n;i++)v.push_back(root->qry(i));
	sort(v.begin(), v.end());
	int in = 0;
	int ans = 2e9;
	for(int i=1;i<=n;i++){
		while(in < (int)v.size() && v[in] <= i)in++;
		//cout << P[i] << ' ' << in - i << '\n';
		ans = min(ans, P[i] + (n - i) - (in - i));
	}
	cout << ans;
}

main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int tc = 1;
	//cin >> tc;
	for(int tc1=1;tc1<=tc;tc1++){
		// cout << "Case #" << tc1 << ": ";
		solve();
	}
}

Compilation message (stderr)

prison.cpp:97:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   97 | main(){
      | ^~~~

• Subtask 1: 0 / 15
• Subtask 2: 10 / 10
• Subtask 3: 0 / 20
• Subtask 4: 0 / 10
• Subtask 5: 0 / 25
• Subtask 6: 0 / 20