Submission #935678

#	Time	Username	Problem	Language	Result	Execution time	Memory
935678		Warinchai	Martian DNA (BOI18_dna)	C++14	100 / 100	38 ms	4912 KiB

dna

#include<bits/stdc++.h>
using namespace std;
int ar[200005];
int mn[200005];
int temp[200005];
int n,k,r;
bool check(int m){
    int cnt=0;
    for(int i=0;i<k;i++)temp[i]=0;
    for(int i=0;i<k;i++)if(mn[i]==0)cnt++;
    for(int i=1;i<=m;i++){
        temp[ar[i]]++;
        if(temp[ar[i]]==mn[ar[i]])cnt++;
    }
    if(cnt==k)return true;
    //cerr<<m<<" "<<cnt<<"\n";
    for(int i=m+1;i<=n;i++){
        temp[ar[i]]++;
        if(temp[ar[i]]==mn[ar[i]])cnt++;
        temp[ar[i-m]]--;
        if(temp[ar[i-m]]==mn[ar[i-m]]-1)cnt--;
        if(cnt==k)return true;
    }
    return false;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>k>>r;
    for(int i=1;i<=n;i++)cin>>ar[i];
    for(int i=0;i<r;i++){
        int b;cin>>b;
        cin>>mn[b];
    }
    int st=1,en=n,ans=-1;
    while(st<=en){
        int m=(st+en)/2;
        if(check(m)){
            en=m-1;
            ans=m;
        }else{
            st=m+1;
        }
    }
    if(ans==-1)cout<<"impossible";
    else cout<<ans;
}

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 28 / 28
• Subtask 4: 32 / 32