Submission #781621

#	Time	Username	Problem	Language	Result	Execution time	Memory
781621		vjudge1	JJOOII 2 (JOI20_ho_t2)	C++17	100 / 100	10 ms	3040 KiB

ho_t2

#include<bits/stdc++.h>
using namespace std;
#define lalala ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define endl "\n"
#define ll long long
#define pb push_back
#define N 2000005
int owo[N];
int main(){
	lalala;
	int n,k;cin>>n>>k;
	string str;cin>>str;
	vector<int>J,I,bir,iki;
	for(int i=0;i<n;i++){
		owo[i+1]+=owo[i];
		if(str[i]=='O')owo[i+1]++;
		if(str[i]=='J')J.pb(i+1);
		if(str[i]=='I')I.pb(i+1);
	}
	if(J.size()<k||I.size()<k){
		cout<<-1<<endl;
		return 0;
	}
	int why=0,neden=0;
	for(int i=1;i<k;i++){
		why+=J[i]-J[i-1]-1;
		neden+=I[i]-I[i-1]-1;
	}
	bir.pb(why);
	iki.pb(neden);
	for(int i=1;i<J.size()-k+1;i++){
		why-=(J[i]-J[i-1]-1);
		why+=(J[i+k-1]-J[i+k-2]-1);
		bir.pb(why);
	}
	for(int i=1;i<I.size()-k+1;i++){
		neden-=(I[i]-I[i-1]-1);
		neden+=(I[i+k-1]-I[i+k-2]-1);
		iki.pb(neden);
	}
	int ans=1000000000;
	for(int i=0;i<bir.size();i++){
		int yer=J[i],son=J[i+k-1];
		int cur=bir[i];
		int l=upper_bound(I.begin(),I.end(),son)-I.begin(), r=I.size()-1;


		//cout<<yer<<" "<<son<<" "<<l<<" "<<r<<" "<<I[l]<<" "<<i<<" "<<i+k-1<<endl;
		if(l==I.size())continue;
		while(l<r){
			int mid=(l+r)/2;
			int m=I[mid];
			//cout<<l<<" a "<<r<<" "<<mid<<" "<<m<<" "<<owo[m]<<endl;
			if(owo[m]-owo[son]>=k){
				r=mid;
			}
			else l=mid+1;
		}

		if(l>=iki.size()||owo[I[l]]-owo[son]<k)continue;
		cur+=iki[l];
		cur+=I[l]-son-1-k;

		//cout<<yer<<" "<<son<<" "<<l<<" "<<I[l]<<" "<<i<<" "<<i+k-1<<endl;
		//cout<<bir[i]<<" "<<iki[l]<<" "<<I[l]-son-1-k<<" "<<cur<<endl;
		ans=min(ans,cur);
	}
	if(ans==1000000000)ans=-1;
	cout<<ans<<endl;

}

Compilation message (stderr)

ho_t2.cpp: In function 'int main()':
ho_t2.cpp:20:13: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   20 |  if(J.size()<k||I.size()<k){
      |     ~~~~~~~~^~
ho_t2.cpp:20:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   20 |  if(J.size()<k||I.size()<k){
      |                 ~~~~~~~~^~
ho_t2.cpp:31:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |  for(int i=1;i<J.size()-k+1;i++){
      |              ~^~~~~~~~~~~~~
ho_t2.cpp:36:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |  for(int i=1;i<I.size()-k+1;i++){
      |              ~^~~~~~~~~~~~~
ho_t2.cpp:42:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |  for(int i=0;i<bir.size();i++){
      |              ~^~~~~~~~~~~
ho_t2.cpp:49:7: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |   if(l==I.size())continue;
      |      ~^~~~~~~~~~
ho_t2.cpp:60:7: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |   if(l>=iki.size()||owo[I[l]]-owo[son]<k)continue;
      |      ~^~~~~~~~~~~~
ho_t2.cpp:43:7: warning: unused variable 'yer' [-Wunused-variable]
   43 |   int yer=J[i],son=J[i+k-1];
      |       ^~~

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