Submission #251362

#	Time	Username	Problem	Language	Result	Execution time	Memory
251362		shenxy	Password (RMI18_password)	C++14	100 / 100	255 ms	744 KiB

password

#include <algorithm>
#include <string>
using namespace std;
int cnt[26];
int query(string str);
string dnc(int s, int e) {
	if (s == e) {
		string ans = "";
		for (int i = 0; i < cnt[s]; ++i) ans.push_back('a' + s);
		return ans;
	}
	string l = dnc(s, (s + e) / 2), r = dnc((s + e) / 2 + 1, e);
	int ptr = 0;
	for (char c: r) {
		string x = l;
		x.insert(ptr, 1, c);
		while (query(x) != x.length()) x = l, x.insert(++ptr, 1, c);
		l = x;
		++ptr;
	}
	return l;
}
string guess(int N, int S) {
	for (int i = 0; i < S; ++i) {
		string Q = "";
		for (int j = 0; j < N; ++j) Q.push_back('a' + i);
		cnt[i] = query(Q);
	}
	return dnc(0, S - 1);
}

Compilation message (stderr)

password.cpp: In function 'std::__cxx11::string dnc(int, int)':
password.cpp:17:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while (query(x) != x.length()) x = l, x.insert(++ptr, 1, c);
          ~~~~~~~~~^~~~~~~~~~~~~

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