Submission #959797

#	Time	Username	Problem	Language	Result	Execution time	Memory
959797		happy_node	JJOOII 2 (JOI20_ho_t2)	C++17	100 / 100	8 ms	2268 KiB

ho_t2

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

const int MX=2e5+5;
int N,K;
string s;

vector<int> pos[3];

int main() {
	cin.tie(0); ios_base::sync_with_stdio(0);

	cin>>N>>K;
	cin>>s;

	for(int i=0;i<N;i++) {
		if(s[i]=='J') pos[0].push_back(i);
		if(s[i]=='O') pos[1].push_back(i);
		if(s[i]=='I') pos[2].push_back(i);
	}

	int ans=2e9;
	for(int i=0;i+K-1<pos[1].size();i++) {
		int p=pos[1][i+K-1];
		auto it=upper_bound(pos[2].begin(),pos[2].end(),p)-pos[2].begin();
		if(it+K-1>=pos[2].size()) continue;
		auto it2=lower_bound(pos[0].begin(),pos[0].end(),pos[1][i])-pos[0].begin();
		if(it2==0) continue;
		it2--;
		if(it2-K+1<0) continue;
		ans=min(ans,pos[2][it+K-1]-pos[0][it2-K+1]+1-3*K);
	}

	if(ans==2e9) {
		cout<<-1<<'\n';
		return 0;
	}
	cout<<ans<<'\n';
}

Compilation message (stderr)

ho_t2.cpp: In function 'int main()':
ho_t2.cpp:23:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |  for(int i=0;i+K-1<pos[1].size();i++) {
      |              ~~~~~^~~~~~~~~~~~~~
ho_t2.cpp:26:12: warning: comparison of integer expressions of different signedness: 'long int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |   if(it+K-1>=pos[2].size()) continue;
      |      ~~~~~~^~~~~~~~~~~~~~~

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