Submission #95636

#	Time	Username	Problem	Language	Result	Execution time	Memory
95636		jamielim	Combo (IOI18_combo)	C++14	100 / 100	86 ms	560 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"

std::string guess_sequence(int N){
    if(N==1){
        if(press("A")==1)return "A";
        if(press("B")==1)return "B";
        if(press("X")==1)return "X";
        return "Y";
    }
    std::string test="";
    std::string ans="";
    if(press("AB")!=0){
        if(press("A")==1){
            for(int i=0;i<4*N;i++)test.push_back('A');
            ans.push_back('A');
        }else{
            for(int i=0;i<4*N;i++)test.push_back('B');
            ans.push_back('B');
        }
    }else{
        if(press("X")==1){
            for(int i=0;i<4*N;i++)test.push_back('X');
            ans.push_back('X');
        }else{
            for(int i=0;i<4*N;i++)test.push_back('Y');
            ans.push_back('Y');
        }
    }
    //2
    for(int i=1;i<N-1;i++){ //N-2
        if(ans[0]=='A'){
            test[i]='B';test[i+1]='B';
            test[N+i]='B';test[N+i+1]='X';
            test[2*N+i]='B';test[2*N+i+1]='Y';
            test[3*N+i]='X';
            int k=press(test);
            test[i+1]='A'; test[N+i+1]='A'; test[2*N+i+1]='A';
            if(k==i+2){
                test[3*N+i]='B';
                ans.push_back('B');
            }else if(k==i+1){
                test[i]='X'; test[N+i]='X'; test[2*N+i]='X';
                ans.push_back('X');
            }else{
                test[i]='Y'; test[N+i]='Y'; test[2*N+i]='Y'; test[3*N+i]='Y';
                ans.push_back('Y');
            }
        }else if(ans[0]=='B'){
            test[i]='A';test[i+1]='A';
            test[N+i]='A';test[N+i+1]='X';
            test[2*N+i]='A';test[2*N+i+1]='Y';
            test[3*N+i]='X';
            int k=press(test);
            test[i+1]='B'; test[N+i+1]='B'; test[2*N+i+1]='B';
            if(k==i+2){
                test[3*N+i]='A';
                ans.push_back('A');
            }else if(k==i+1){
                test[i]='X'; test[N+i]='X'; test[2*N+i]='X';
                ans.push_back('X');
            }else{
                test[i]='Y'; test[N+i]='Y'; test[2*N+i]='Y'; test[3*N+i]='Y';
                ans.push_back('Y');
            }
        }else if(ans[0]=='X'){
            test[i]='A';test[i+1]='A';
            test[N+i]='A';test[N+i+1]='B';
            test[2*N+i]='A';test[2*N+i+1]='Y';
            test[3*N+i]='B';
            int k=press(test);
            test[i+1]='X'; test[N+i+1]='X'; test[2*N+i+1]='X';
            if(k==i+2){
                test[3*N+i]='A';
                ans.push_back('A');
            }else if(k==i+1){
                test[i]='B'; test[N+i]='B'; test[2*N+i]='B';
                ans.push_back('B');
            }else{
                test[i]='Y'; test[N+i]='Y'; test[2*N+i]='Y'; test[3*N+i]='Y';
                ans.push_back('Y');
            }
        }else{
            test[i]='A';test[i+1]='A';
            test[N+i]='A';test[N+i+1]='B';
            test[2*N+i]='A';test[2*N+i+1]='X';
            test[3*N+i]='B';
            int k=press(test);
            test[i+1]='Y'; test[N+i+1]='Y'; test[2*N+i+1]='Y';
            if(k==i+2){
                test[3*N+i]='A';
                ans.push_back('A');
            }else if(k==i+1){
                test[i]='B'; test[N+i]='B'; test[2*N+i]='B';
                ans.push_back('B');
            }else{
                test[i]='X'; test[N+i]='X'; test[2*N+i]='X'; test[3*N+i]='X';
                ans.push_back('X');
            }
        }
    }
    if(ans[0]=='A'){
        ans.push_back('B');
        if(press(ans)==N)return ans;
        ans[N-1]='X';
        if(press(ans)==N)return ans;
        ans[N-1]='Y'; return ans;
    }else if(ans[0]=='B'){
        ans.push_back('A');
        if(press(ans)==N)return ans;
        ans[N-1]='X';
        if(press(ans)==N)return ans;
        ans[N-1]='Y'; return ans;
    }else if(ans[0]=='X'){
        ans.push_back('A');
        if(press(ans)==N)return ans;
        ans[N-1]='B';
        if(press(ans)==N)return ans;
        ans[N-1]='Y'; return ans;
    }else{
        ans.push_back('A');
        if(press(ans)==N)return ans;
        ans[N-1]='B';
        if(press(ans)==N)return ans;
        ans[N-1]='X'; return ans;
    }
    //2
    return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 95 / 95