Submission #111063

#	Time	Username	Problem	Language	Result	Execution time	Memory
111063		Plasmatic	Combo (IOI18_combo)	C++11	100 / 100	43 ms	452 KiB

combo

//============================================================================
// Name        : ioi18p1.cpp
// Author      : Daxi the Taxi
// Version     :
// Copyright   : ALL YOUR CODE IS BELONG TO US
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> p;

#ifndef ONLINE_JUDGE
int press(string s);
#endif

string guess_sequence(int n){
        string cur = "",
                        ava[3];

        // Guessing first letter
        int ret = press("AB");
        if(ret){
                ret = press("A");
                if(ret)
                        cur = "A", ava[0] = "B", ava[1] = "X", ava[2] = "Y";
                else
                        cur = "B", ava[0] = "A", ava[1] = "X", ava[2] = "Y";
        }
        else{
                ret = press("X");
                if(ret)
                        cur = "X", ava[0] = "A", ava[1] = "B", ava[2] = "Y";
                else
                        cur = "Y", ava[0] = "A", ava[1] = "B", ava[2] = "X";
        }

        // Rest of it
        for (int i = 1; i < n - 1; ++i) {
                ret = press(cur + ava[0] + ava[0] + cur + ava[1] + ava[0] + cur + ava[1] + ava[1]) - i;

                if(ret == 1){
                        ret = press(cur + ava[0] + ava[2]) - i;

                        if(ret == 0) cur += ava[1] + ava[2];
                        else if(ret == 1) cur += ava[0] + ava[1];
                        else cur += ava[0] + ava[2];

                        i++;
                }
                else if(ret == 2){
                        ret = press(cur + ava[1] + ava[0]) - i;

                        if(ret == 0) cur += ava[0] + ava[0];
                        else if(ret == 1) cur += ava[1] + ava[1];
                        else cur += ava[1] + ava[0];

                        i++;
                }
                else cur += ava[2];
        }

        // Last letter if required
        int sz = cur.size();
        if(sz < n){
                ret = press(cur + ava[0]);
                if(ret > sz) cur += ava[0];
                else{
                        ret = press(cur + ava[1]);
                        if(ret > sz) cur += ava[1];
                        else cur += ava[2];
                }
        }

        return cur;
}

#ifdef WHEEEEEEE
const int N = 20;
const string STR = "ABYXXBYXYBBYXBYXXYBB";
int presscnt = 0;

int press(string s){
        int sz = s.length(), ptr = 0, best = INT_MIN;
        assert(sz <= N << 2);
        for (int i = 0; i < sz; ++i) {
                if(s[i] == STR[ptr])
                        ptr++;
                else
                        ptr = 0;

                best = max(best, ptr);
                if(ptr == N) ptr = 0;
        }
        presscnt++;
        return best;
}

int main(){
        printf("%s\n", guess_sequence(N).c_str());
        printf("presscnt=%d\n", presscnt);
        return 0;
}
#endif

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