Submission #1052282

#	Time	Username	Problem	Language	Result	Execution time	Memory
1052282		Minbaev	JJOOII 2 (JOI20_ho_t2)	C++17	0 / 100	0 ms	348 KiB

ho_t2

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> 
 
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
 
using namespace std;
using namespace __gnu_pbds;
 
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define s second
#define int long long
#define ll long long
#define pii pair<int,int>
#define ar array
 
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
 
template<class T> using st = tree<T, null_type, less_equal<T>, 
rb_tree_tag, tree_order_statistics_node_update>;
 
const int inf = 1e17 + 7;
const int mod = 1e9 + 7;
const int N = 3e5 + 5;
const int md = 998244353;
 
int binpow(int a, int b){
	if(b == 0)return 1;
	if(b % 2 == 0){
		int c = binpow(a,b/2);
		return (c*c)%mod;
	}
	return (binpow(a,b-1)*a)%mod;
}
 
int divi(int a, int b){
	return (a*(binpow(b,mod-2)))%mod;
}
 
int n,m,k;
 
void solve(){
	
	cin >> n >> m;
	
	string str, a;
	cin >> str;

	int pref[n][3]{}, last[n]{};
	vector<vector<int>>v(3);
	vector<bool>flag(n);
	
	for(int i = 0;i<n;i++){
		if(str[i] == 'J'){
			pref[i][0] += 1;
			v[0].pb(i);
		}
		if(str[i] == 'O'){
			pref[i][1] += 1;
			v[1].pb(i);
		}
		if(str[i] == 'I'){
			pref[i][2] += 1;
			v[2].pb(i);
		}
		if(i > 0){
			pref[i][0] += pref[i-1][0];
			pref[i][1] += pref[i-1][1];
			pref[i][2] += pref[i-1][2];
		}
	}
	
	int mn = inf;
	
	for(int i = 0;i<n;i++){
		if(str[i] == 'J'){
			if(pref[i][0] >= m)last[i] = v[0][pref[i][0]-m];
		}
		if(str[i] == 'O' && pref[i][1] >= m){
			int l = 0, r = v[0].size()-1, ans = -1;
			while(l <= r){
				int mid = (l+r)/2;
				
				if(v[0][mid] > v[1][pref[i][1]-2])r = mid - 1;
				else {
					ans = v[0][mid];
					l = mid + 1;
				}
			}
			if(ans != -1 && pref[ans][0] >= m){
				last[i] = last[ans];
				flag[i] = true;
			}
		}
		if(str[i] == 'I' && pref[i][2] >= m){
			int l = 0, r = v[1].size()-1, ans = -1;
			while(l <= r){
				int mid = (l+r)/2;
				
				if(v[1][mid] > v[2][pref[i][2]-2])r = mid - 1;
				else {
					ans = v[1][mid];
					l = mid + 1;
				}
			}
			if(ans != -1 && flag[ans]){
				umin(mn, (i-last[ans]+1)-m*3);
			}
			//~ cout << ans << " ";
		}
	}
	
	cout << ((mn == inf) ? -1 : mn) << "\n";
	
	//~ for(int i = 0;i<n;i++){
		//~ cout << flag[i] << " " << last[i] << "\n";
	//~ }
	
	
	
 
}
/*
5 4
35 100
70 70
45 15
80 40
20 95
20 50 0
10 10 0
60 60 0
0 100 0
*/
 signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int tt=1;//cin>>tt;
	while(tt--)solve();
 
}

• Subtask 1: 0 / 1
• Subtask 2: 0 / 12
• Subtask 3: 0 / 87