Submission #433412

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Source Code Expand

#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <deque>
#include <complex>
#include <stack>
#include <queue>
#include <cstdio>
#include <cctype>
#include <cstring>
#include <ctime>
#include <iterator>
#include <bitset>
#include <numeric>
#include <list>
#include <iomanip>
 
#if __cplusplus >= 201103L
#include <array>
#include <tuple>
#include <initializer_list>
#include <unordered_set>
#include <unordered_map>
#include <forward_list>
 
#define cauto const auto&
#endif
 
using namespace std;
 
 
typedef long long LL;
typedef pair<int,int> pii;
typedef pair<LL,LL> pll;
 
typedef vector<int> vint;
typedef vector<vector<int> > vvint;
typedef vector<long long> vll, vLL;
typedef vector<vector<long long> > vvll, vvLL;
 
#define VV(T) vector<vector< T > >
 
template <class T>
void initvv(vector<vector<T> > &v, int a, int b, const T &t = T()){
v.assign(a, vector<T>(b, t));
}
 
template <class F, class T>
void convert(const F &f, T &t){
stringstream ss;
ss << f;
ss >> t;
}
 
 
#define rep(i,n) for(int i=0;i<int(n);++i)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
 
 
#define MOD 1000000007LL
#define EPS 1e-8
 
int main(){
	string s;
	int n;
	cin>>s>>n;
	
	set<string> cand;
	rep(i,s.length()){
		rep(j,s.length()){
			string ss;
			ss += s[i];
			ss += s[j];
			cand.insert(ss);
		}
	}
	
	set<string>::iterator it = cand.begin();
	rep(i,n-1) it++;
	cout<<*it<<endl;
	
	return 0;
}

Submission Info

Judge Result