Submission #331746

#	Time	Username	Problem	Language	Result	Execution time	Memory
331746		dolphingarlic	Password (RMI18_password)	C++14	100 / 100	290 ms	808 KiB

password

#include <string>
using namespace std;

int query(string str);

string solve(int l, int r, int n) {
	if (l == r) {
		string to_guess = "";
		for (int i = 0; i < n; i++) to_guess += 'a' + l;
		int len = query(to_guess);
		return string(len, 'a' + l);
	} else {
		int mid = (l + r) / 2;
		string a = solve(l, mid, n), b = solve(mid + 1, r, n);
		int a_ptr = 0, b_ptr = 0;
		string known = "";
		while (a_ptr < a.size() && b_ptr < b.size()) {
			string to_guess = known + a[a_ptr] + b.substr(b_ptr);
			int prev_len = known.size() + b.size() - b_ptr;
			if (query(to_guess) > prev_len) known += a[a_ptr++];
			else known += b[b_ptr++];
		}
		if (a_ptr < a.size()) known += a.substr(a_ptr);
		else known += b.substr(b_ptr);
		return known;
	}
}

string guess(int n, int s) { return solve(0, s - 1, n); }

Compilation message (stderr)

password.cpp: In function 'std::string solve(int, int, int)':
password.cpp:17:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |   while (a_ptr < a.size() && b_ptr < b.size()) {
      |          ~~~~~~^~~~~~~~~~
password.cpp:17:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |   while (a_ptr < a.size() && b_ptr < b.size()) {
      |                              ~~~~~~^~~~~~~~~~
password.cpp:23:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |   if (a_ptr < a.size()) known += a.substr(a_ptr);
      |       ~~~~~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 30 / 30
• Subtask 5: 20 / 20