Submission #230070

#	Time	Username	Problem	Language	Result	Execution time	Memory
230070		AMO5	JJOOII 2 (JOI20_ho_t2)	C++98	100 / 100	15 ms	2052 KiB

ho_t2

// READ & UNDERSTAND
// ll, int overflow, array bounds, memset(0)
// special cases (n=1?), n+1 (1-index)
// do smth instead of nothing & stay organized
// WRITE STUFF DOWN

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end() 
#define MOD 1000000007

typedef long long ll;
typedef pair <int, int> ii;
typedef pair <ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef long double ld;

ll INF=LLONG_MAX;

int const mxn=2e5+5;
vi dp[3]; //JOI,pos

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    //freopen("input.txt","r",stdin); freopen("output.txt","w",stdout);
	int n,k; string s;
	cin >> n >> k >> s;
	for(int i=0; i<n; i++){
		if(s[i]=='J')dp[0].pb(i);
		else if(s[i]=='O')dp[1].pb(i);
		else dp[2].pb(i);
	}
	int ans=1e9;
	for(int i=0; i<(int)dp[0].size()-k+1; i++){
		int posini = dp[0][i];
		int posj = dp[0][i+k-1];
		int poso = upper_bound(all(dp[1]),posj)-dp[1].begin();
		if(poso==(int)dp[1].size())break;
		poso += k-1; 
		if(poso>=(int)dp[1].size())break;
		poso = dp[1][poso];
		int posi = upper_bound(all(dp[2]),poso)-dp[2].begin();
		if(posi==(int)dp[2].size())break;
		posi += k-1;
		if(posi>=(int)dp[2].size())break;
		posi = dp[2][posi];
		ans = min(ans, posi-posini+1-k*3);
	}
	
	if(ans==1e9)ans=-1;
	cout << ans << endl;
}	

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