Submission #885308

#	Time	Username	Problem	Language	Result	Execution time	Memory
885308		Irate	Combo (IOI18_combo)	C++14	97 / 100	13 ms	1728 KiB

combo

#include "combo.h"
#include<bits/stdc++.h>
using namespace std;


// string guess_sequence(int N);


// namespace {

// constexpr int MAX_N = 2000;
// constexpr int MAX_NUM_MOVES = 8000;

// int N;
// std::string S;

// int num_moves;

// void wrong_answer(const char *MSG) {
//   printf("Wrong Answer: %s\n", MSG);
//   exit(0);
// }

// }  // namespace

// int press(std::string p) {
//   if (++num_moves > MAX_NUM_MOVES) {
//     wrong_answer("too many moves");
//   }
//   int len = p.length();
//   if (len > 4 * N) {
//     wrong_answer("invalid press");
//   }
//   for (int i = 0; i < len; ++i) {
//     if (p[i] != 'A' && p[i] != 'B' && p[i] != 'X' && p[i] != 'Y') {
//       wrong_answer("invalid press");
//     }
//   }
//   int coins = 0;
//   for (int i = 0, j = 0; i < len; ++i) {
//     if (j < N && S[j] == p[i]) {
//       ++j;
//     } else if (S[0] == p[i]) {
//       j = 1;
//     } else {
//       j = 0;
//     }
//     coins = std::max(coins, j);
//   }
//   return coins;
// }

// int main() {
//   char buffer[MAX_N + 1];
//   if (scanf("%s", buffer) != 1) {
//     fprintf(stderr, "Error while reading input\n");
//     exit(1);
//   }
//   S = buffer;
//   N = S.length();

//   num_moves = 0;
//   std::string answer = guess_sequence(N);
//   if (answer != S) {
//     wrong_answer("wrong guess");
//     exit(0);
//   }
//   printf("Accepted: %d\n", num_moves);
//   return 0;
// }
string construct(string &d, string &pref){
    string tempo = "";
    for(int i = 0;i < 3;++i){
        tempo += pref;
        tempo += d[0];
        tempo += d[i];
    }   
    tempo += pref;
    tempo += d[1]; 
    return tempo;
}
string guess_sequence(int N) {
    string p = "";
    char c = 'A';
    if(press("A")){
        p += 'A';
        c = 'A';
    }
    else if(press("B")){
        p += 'B';
        c = 'B';
    }
    else if(press("X")){
        p += 'X';
        c = 'X';
    }
    else{
        p += 'Y';
        c = 'Y';
    }
    string s = "ABXY", d = "";
    for(int i = 0;i < 4;++i){
        if(c == s[i])continue;
        d += s[i];
    }
    for(int i = 1;i < N;++i){
        bool check = 0;
        if(p.size() <= N - 2){
            string tempo = construct(d, p);
            int num = press(tempo);
            if(num >= p.size() + 2){
                p += d[0];
            }
            else if(num >= p.size() + 1){
                p += d[1];
            }
            else{
                p += d[2];
            }
        }
        else{
            bool check = 0;
            for(int j = 0;j < 2;++j){
                p += d[j];
                if(press(p) >= p.size()){
                    check = 1;
                    break;
                }
                p.pop_back();
            }
            if(!check){
                p += d[2];
            }
        }
    }
    return p;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:108:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  108 |         if(p.size() <= N - 2){
      |            ~~~~~~~~~^~~~~~~~
combo.cpp:111:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  111 |             if(num >= p.size() + 2){
      |                ~~~~^~~~~~~~~~~~~~~
combo.cpp:114:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  114 |             else if(num >= p.size() + 1){
      |                     ~~~~^~~~~~~~~~~~~~~
combo.cpp:125:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  125 |                 if(press(p) >= p.size()){
      |                    ~~~~~~~~~^~~~~~~~~~~
combo.cpp:107:14: warning: unused variable 'check' [-Wunused-variable]
  107 |         bool check = 0;
      |              ^~~~~

• Subtask 1: 5 / 5
• Subtask 2: 92 / 95