Submission #742441

#	Time	Username	Problem	Language	Result	Execution time	Memory
742441		penguin133	The short shank; Redemption (BOI21_prison)	C++17	0 / 100	79 ms	21028 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);
}*/
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];
	}
	int in = n;
	vector <int> v;
	for(int i=n;i>=1;i--){
		in = min(in, i);
		while (in >= 1 && A[in] + i > t)in--;
		S[i] = in;
		v.push_back(in);
	}
	sort(v.begin(), v.end());
	in = 0;
	int ans = 2e9;
	for(int i=1;i<=n;i++){
		while(in < (int)v.size() && v[in] <= i)in++;
		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:58:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   58 | main(){
      | ^~~~

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