Submission #1038744

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038744		Warinchai	COVID tests (CEOI24_covid)	C++14	52.27 / 100	1695 ms	600 KiB

Main

#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC target("avx2")
using namespace std;
int n,t;
double p;
int use=0;
int ask(string v){
    //use++;
    cout<<"Q ";
    cout<<v;
    cout<<endl;
    //cerr<<"input:"<<endl;
    char ans;
    cin>>ans;
    //cerr<<ans<<endl;
    return ans=='P'?1:0;
}
string temp;
string ans;
void fans(int st,int en){
    //cerr<<st<<" "<<en<<endl;
    if(st==en){
        temp[st]='1';
        ans[st]=ask(temp)?'1':'0';
        temp[st]='0';
        return;
    }
    if(st>en)return;
    int m=(st+en)/2;
    for(int i=st;i<=m;i++)temp[i]='1';
    bool tans;tans=ask(temp);
    for(int i=st;i<=m;i++)temp[i]='0';
    if(tans){
        if(st==m)ans[st]='1';
        else fans(st,m);

        for(int i=m+1;i<=en;i++)temp[i]='1';
        tans=ask(temp);
        for(int i=m+1;i<=en;i++)temp[i]='0';
        if(tans){
            if(m+1==en)ans[en]='1';
            else fans(m+1,en);
        }
    }else{
        if(m+1==en)ans[en]='1';
        else fans(m+1,en);
    }
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin>>n>>p>>t;
    temp=string(n,'0');
    int prob=max(1,(int)p*n);
    prob=min(n,prob);
    int div=n/prob;
    int val=0;
    for(;val<=10;val++){
        if((1<<val)>div)break;
    }
    val--;
    div=(1<<val);
    //cerr<<"prob:"<<prob<<endl;
    //cerr<<"div:"<<div<<endl;
    while(t--){
        //cerr<<"work"<<endl;
        ans=string(n,'0');
        use=0;

        for(int i=1;i<prob;i++){
            cerr<<"prob-"<<i<<endl;
            string t(n,'0');
            for(int j=div*(i-1);j<=div*i-1;j++)t[j]='1';
            if(div*i-1==div*(i-1)||ask(t))fans(div*(i-1),div*i-1);
            for(int j=div*(i-1);j<=div*i-1;j++)t[j]='0';
        }
        string temp(n,'0');
        for(int j=div*(prob-1);j<=n-1;j++)temp[j]='1';
        if(div*(prob-1)==n-1||ask(temp))fans(div*(prob-1),n-1);
        cout<<"A ";
        cout<<ans;
        cout<<endl;
        char res;
        cin>>res;
        //cerr<<"use:"<<use<<endl;
        if(res=='W')break;
    }
}

• Subtask 0: 0 / 0
• Subtask 1: 10 / 10
• Subtask 2: 42.270000003 / 90