Submission #1052199

#	Time	Username	Problem	Language	Result	Execution time	Memory
1052199		khanhtb	Combo (IOI18_combo)	C++14	5 / 100	1 ms	344 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"
#define ll long long
#define ull unsigned long long
#define ld long double
#define pb push_back
#define pf push_front
#define vi vector<ll>
#define vii vector<vi>
#define pll pair<ll, ll>
#define vpll vector<pll>
#define all(a) a.begin(), a.end()
#define fi first
#define se second
using namespace std;
const ll mod = 1e9+7; 
const ll inf = 2e18;
const ll B = 320;
const ll N = 1e5+8;
string ans = "";
vector<string> bt = {"A","B","X","Y"};
string guess_sequence(int N){
    int fid = -1;
    if(press("AB")){
        if(press("A")) fid = 0;
        else fid = 1;
    }
    else{
        if(press("X")) fid = 2;
        else fid = 3;
    }
    ans += bt[fid];
    int x = -1, y = -1, z = -1;
    for(int i = 0; i < 4; i++){
        if(i == fid) continue;
        if(x == -1) x = i;
        else if(y == -1) y = i;
        else z = i;
    }
    for(int i = 2; i < N; i++){
        string query = (ans + bt[x]) + (ans + bt[y] + bt[x]) + (ans + bt[y] + bt[y]) + (ans + bt[y] + bt[z]);
        int rep = press(query);
        if(rep == ans.size()+1) ans += bt[x];
        else if(rep == ans.size()+2) ans += bt[y];
        else ans += bt[z];
    }
    string query1 = ans + bt[x], query2 = ans + bt[y];
    if (press(query1) == N) return query1;
    if (press(query2) == N) return query2;
    return ans + bt[z];
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:43:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |         if(rep == ans.size()+1) ans += bt[x];
      |            ~~~~^~~~~~~~~~~~~~~
combo.cpp:44:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |         else if(rep == ans.size()+2) ans += bt[y];
      |                 ~~~~^~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 95