Artifact 6285086493d4d5982f34a780db4c51e2932063d1
#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <functional>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
#include <cassert>
#include <cstring>
#ifdef __GNUC__
#include <ext/hash_map>
#define unordered_map __gnu_cxx::hash_map
#else
#include <unordered_map>
#endif
using namespace std;
typedef long long LL;
typedef complex<double> CMP;
class TheDictionary { public:
string find(int n, int m, int k)
{
if( k <= C(n+m,n) )
return rec(n, m, k);
return "";
}
string rec(int n, int m, int k)
{
if( n+m == 0 )
return "";
if( n==0 )
return "z" + rec(n, m-1, k);
if( m==0 )
return "a" + rec(n-1, m, k);
LL c = C(n+m-1, m);
if( k <= c )
return "a" + rec(n-1, m, k);
return "z" + rec(n, m-1, k - c);
}
LL C(int n, int k)
{
k = min(k, n-k);
LL v = 1;
for(int i=1; i<=k; ++i) {
v = v * (n+1-i) / i;
if( v >= (1LL<<50) )
return v;
}
return v;
}
};
// BEGIN CUT HERE
#include <ctime>
double start_time; string timer()
{ ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
{ os << "{ ";
for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
void verify_case(const string& Expected, const string& Received) {
bool ok = (Expected == Received);
if(ok) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl;
cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
#define END verify_case(_, TheDictionary().find(n, m, k));}
int main(){
CASE(0)
int n = 2;
int m = 2;
int k = 2;
string _ = "azaz";
END
CASE(1)
int n = 2;
int m = 2;
int k = 6;
string _ = "zzaa";
END
CASE(2)
int n = 10;
int m = 10;
int k = 1000000000;
string _ = "";
END
CASE(3)
int n = 7;
int m = 4;
int k = 47;
string _ = "aaazazaazaz";
END
/*
CASE(4)
int n = ;
int m = ;
int k = ;
string _ = ;
END
CASE(5)
int n = ;
int m = ;
int k = ;
string _ = ;
END
*/
}
// END CUT HERE