# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
755819 | vjudge1 | Password (RMI18_password) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#include <fstream>
#include <iostream>
#include <sstream>
#include <string>
#include <stdlib.h>
#include <assert.h>
#include <bits/stdc++.h>
using namespace std;
#define DEBUG 0
#define MAX_QUERIES 50000
#define MAX_N 5000
#define MAX_SIGMA 26
static string password;
static int n, s, numQueries;
static stringstream msg;
static void end(int success) {
cout << (success ? "SUCCESS! " : "ERROR: ") << msg.str() << endl;
exit(0);
}
int query(string q) {
if (++numQueries > MAX_QUERIES) {
msg << "Could not guess the password with " << MAX_QUERIES << " questions.";
end(0);
}
int len = q.size();
// validation
if (len < 1 || len > n) {
msg << "Query '" << q << "' should have length between 1 and "
<< n << " characters.";
end(0);
}
for (int i = 0; i < len; i++) {
if (q[i] < 'a' || q[i] >= 'a' + s) {
msg << "Illegal character '" << q[i] << "' found.";
end(0);
}
}
// while possible, advance one character in q and find its next
// occurrence in password
int i = 0, j = 0, plen = password.size();
while (i < plen && j < len) {
while ((i < plen) && (password[i] != q[j])) {
i++;
}
if (i < plen) { /* found a match */
i++;
j++;
}
}
if (DEBUG) {
cout << "Question #" << numQueries << " [" << q << "] answer " << j << endl;
}
return j;
}
string guess(int n, int s){
int tab[s];
//cout <<n<<" "<<s<<endl;
for (int i = 0; i < s; ++i)
{
char x=char(i+'a');
string t="";
for (int i = 0; i < n; ++i)
{
t.push_back(x);
}
tab[i]=query(t);
}
int fir=0;
while(tab[fir]==0) fir++;
string res="";
for (int i = 0; i < tab[fir]; ++i)
{
char x=char(fir+'a');
res.push_back(x);
}
for (int i = fir+1; i < s; ++i)
{
for (int j = 0; j < tab[fir]; ++j)
{
int p=res.size();
for (int k = 0; k < p+1; ++k)
{
char x=char(i+'a');
string cur="";
//cout << x<<endl;
for (int i = 0; i <= p; ++i)
{
if (i==k) cur.push_back(x);
if (i==p) continue;
cur.push_back(res[i]);
}//cout << cur<<endl;
if (query(cur)>p){
res=cur;
break;
}
}
}
}//cout << res<<endl;
return res;
}
int main() {
ifstream f("password.in");
f >> n >> s >> password;
f.close();
assert(n && s && !password.empty());
string answer = guess(n, s);
if (DEBUG) {
cout << "Your answer: [" << answer << "]\n";
}
if (answer.compare(password)) {
msg << "Your answer was [" << answer
<< "] which does not match the password [" << password << "].";
end(0);
} else {
msg << "You guessed the password with " << numQueries << " queries.";
end(1);
}
return 0;
}