Submission #653324

#	Time	Username	Problem	Language	Result	Execution time	Memory
653324		inksamurai	The short shank; Redemption (BOI21_prison)	C++17	15 / 100	196 ms	206340 KiB

prison

#include <bits/stdc++.h>
#define int ll
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define rng(i,c,n) for(int i=c;i<n;i++)
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define vec(...) vector<__VA_ARGS__>
#define _3D2ZDxo ios::sync_with_stdio(0),cin.tie(0)
typedef long long ll;
using pii=pair<int,int>;
using vi=vector<int>;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}

void chmin(pii&a,pii b){
	if(a.fi>b.fi){
		a=b;
	}else if(a.fi==b.fi){
		a.se=max(a.se,b.se);
	}
}

void chmin1(int&a,int b){
	a=min(a,b);
}

signed main(){
_3D2ZDxo;
	int n,k,t;
	cin>>n>>k>>t;
	k=min(k,n);
	vi a(n);
	rep(i,n){
		cin>>a[i];
	}
	vi dl(n,-1);
	set<pii> st;
	rep(i,n){
		if(sz(st)){
			auto it=st.lower_bound({i,-1});
			if(it!=st.end()){
				dl[i]=(*it).se;
			}
		}
		int val=t-a[i]+i;
		while(sz(st)){
			auto it=st.begin();
			pii p=*it;
			if(p.fi>val) break;
			st.erase(it);
		}
		st.insert({val,i});
	}
	assert(n<=500);
	// naive_a.cpp 06:26pm
	const int inf=1e9;
	vec(vec(vi)) dp(n,vec(vi)(n,vi(k+1,inf)));
	dp[0][0][1]=(a[0]<=t);
	dp[0][0][0]=(a[0]<=t);
	rng(i,1,n){
		rep(j,n){
			rep(e,k+1){
				// don't add
				{
					int ad=(a[i]<=t?1:(e>0 and j<=dl[i])?1:(e==0 and dl[i]!=-1)?1:0);
					// if(i==n-1 and e==0 and j==0){
					// 	print(dp[i-1][j][e],dl[i],ad);
					// }
					chmin1(dp[i][j][e],dp[i-1][j][e]+ad);
				}
				if(e+1<=k){
					int ad=a[i]<=t;
					chmin1(dp[i][i][e+1],dp[i-1][j][e]+ad);
				}
			}
		}
	}
	int ans=inf;
	rep(j,n){
		rep(e,k+1){
			// if(dp[n-1][j][e]==2){
			// 	print(j,e);
			// }
			ans=min(ans,dp[n-1][j][e]);
		}
	}
	print(ans);
}

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