Submission #710498

#	Time	Username	Problem	Language	Result	Execution time	Memory
710498		That_Salamander	Combo (IOI18_combo)	C++14	5 / 100	1 ms	212 KiB

combo

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <cstring>
#include <queue>
#include <unordered_set>
#include <unordered_map>

#define FOR(var,bound) for(int var = 0; var < bound; var++)
#define FORB(var,lb,ub) for (int var = lb; var < ub; var++)
#define FORR(var,bound) for(int var = bound-1; var >= 0; var--)

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef pair<int, int> pii;

int press(string p);

string guess_sequence(int n) {
    string curr;
    vector<string> others;

    if (press("AB")) {
        if (press("A")) {
            curr = "A";
            others = {"B", "X", "Y"};
        } else {
            curr = "B";
            others = {"A", "X", "Y"};
        }
    } else if (press("X")) {
        curr = "X";
        others = {"A", "B", "Y"};
    } else {
        curr = "Y";
        others = {"A", "B", "X"};
    }

    while (curr.length() < n - 1) {
        int res = press(
            curr + others[0] + 
            curr + others[1] + others[0] + 
            curr + others[1] + others[1] + 
            curr + others[1] + others[2]
        ) - curr.size();

        if (res == 0) {
            curr += others[2];
        } else if (res == 1) {
            curr += others[0];
        } else {
            curr += others[1];
        }
    }

    if (press(curr + others[0]) == n) {
        curr += others[0];
    } else if (press(curr + others[1]) == n) {
        curr += others[1];
    } else {
        curr += others[2];
    }

    return curr;
}

#ifdef LOCAL_TEST
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);

  if (num_moves <= N + 2) {
    printf("Big Win!!!!\n");
  } else {
    printf("Not 100% :(\n");
  }
  return 0;
}

#endif

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:46:26: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   46 |     while (curr.length() < n - 1) {
      |            ~~~~~~~~~~~~~~^~~~~~~

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