Submission #1024180

#	Time	Username	Problem	Language	Result	Execution time	Memory
1024180		ksu2009en	Combo (IOI18_combo)	C++14	100 / 100	25 ms	2140 KiB

combo

#include <iostream>
#include <vector>
#include <string>
#include <math.h>
#include <cmath>
#include <iomanip>
#include <cstdio>
#include <algorithm>
#include <numeric>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <deque>
#include <bitset>
#include <cstring>
#include <unordered_map>

using namespace std;
typedef long long ll;

#include "combo.h"

//int press(string p){
//
//    return 0;
//}

string guess_sequence(int n){
    string ans;
    
    if(n == 1){
        if(press("A"))
            ans = "A";
        else if(press("B"))
            ans = "B";
        else if(press("X"))
            ans = "X";
        else
            ans = "Y";
        return ans;
    }
    
    ll f = press("AB");
    
    if(f == 2)
        ans = "A";
    else if(f == 0){
        // x or y
        
        if(press("XA") == 0)
            ans = "Y";
        else
            ans = "X";
    }
    else{
        // a or b
        
        if(press("AX") == 0)
            ans = "B";
        else
            ans = "A";
    }
    
    vector<string> vec, v = {"A", "B", "X", "Y"};
    for(auto i: v)
        if(i != ans)
            vec.push_back(i);
    
    for(int i = 1; i <= n - 2; i++){
        string res = ans + vec[0];
        res += ans + vec[1] + vec[0];
        res += ans + vec[1] + vec[1];
        res += ans + vec[1] + vec[2];
        
        ll c = press(res);
        if(c == ans.size() + 1)
            ans += vec[0];
        else if(c == ans.size() + 2)
            ans += vec[1];
        else
            ans += vec[2];
    }
    
    string res = ans + vec[0];
    if(press(res) == n)
        ans += vec[0];
    else{
        res = ans + vec[1];
        
        if(press(res) == n)
            ans += vec[1];
        else
            ans += vec[2];
    }
    
    return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:77:14: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |         if(c == ans.size() + 1)
      |            ~~^~~~~~~~~~~~~~~~~
combo.cpp:79:19: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |         else if(c == ans.size() + 2)
      |                 ~~^~~~~~~~~~~~~~~~~

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