Submission #991393

#	Time	Username	Problem	Language	Result	Execution time	Memory
991393		hirayuu_oj	Combo (IOI18_combo)	C++17	100 / 100	23 ms	1848 KiB

combo

#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define rep2(i,l,r) for(int i=(l); i<(r); i++)
#define all(x) x.begin(),x.end()
using ll=long long;
constexpr ll LINF=(1LL<<62)-(1LL<<31);
#include "combo.h"

std::string guess_sequence(int N) {
    char fir;
    if(press("AB")){
        if(press("A")){
            fir='A';
        }
        else{
            fir='B';
        }
    }
    else{
        if(press("X")){
            fir='X';
        }
        else{
            fir='Y';
        }
    }
    string S="";
    S+=fir;
    vector<string> use;
    for(string i:{"A","B","X","Y"}){
        if(i!=S)use.emplace_back(i);
    }
    if(N==1)return S;
    rep(i,N-2){
        string now=S+use[0]+S+use[1]+use[0]+S+use[1]+use[1]+S+use[1]+use[2];
        int coin=press(now);
        if(coin==i+1){
            S+=use[2];
        }
        else if(coin==i+2){
            S+=use[0];
        }
        else{
            S+=use[1];
        }
    }
    if(press(S+use[1])==N){
        S+=use[1];
    }
    else{
        if(press(S+use[2])==N){
            S+=use[2];
        }
        else{
            S+=use[0];
        }
    }
    return S;
}

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