Submission #532530

#	Time	Username	Problem	Language	Result	Execution time	Memory
532530		amunduzbaev	JJOOII 2 (JOI20_ho_t2)	C++17	100 / 100	14 ms	4692 KiB

ho_t2

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

#define ar array

const int N = 2e5 + 5;
int dp[3][N];

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	int n, k; cin>>n>>k;
	string s; cin>>s;
	vector<int> a(n);
	for(int i=0;i<n;i++){
		if(s[i] == 'J') a[i] = 0;
		if(s[i] == 'O') a[i] = 1;
		if(s[i] == 'I') a[i] = 2;
	}
	
	memset(dp, -1, sizeof dp);
	for(int j=0;j<3;j++){
		vector<int> p;
		for(int i=0;i<n;i++){
			if(a[i] == j) p.push_back(i);
		} p.push_back(n);
		
		for(int l=k-1;l+1<(int)p.size();l++){
			for(int i=p[l];i<p[l+1];i++) dp[j][i] = p[l-k+1];
		}
	}
	
	int res = 1e9;
	for(int i=0;i<n;i++){
		int l = i;
		for(int j=2;~j && l >= 0;j--){
			l = dp[j][l];
			if(j) l--;
		}
		
		if(l >= 0){
			res = min(res, i - l + 1);
		}
	}
	
	if(res == 1e9) cout<<-1<<"\n";
	else cout<<res - 3 * k<<"\n";
}

• Subtask 1: 1 / 1
• Subtask 2: 12 / 12
• Subtask 3: 87 / 87