Submission #2497675

---

Source Code Expand

#include <bits/stdc++.h>
#define f first
#define s second
#define mp make_pair
#define pb push_back
#define ll long long
using namespace std;

string in;
int k;
vector<int>v;
vector<int>ans;

int main()
{
	cin.sync_with_stdio(0);		cin.tie(0);		cout.tie(0);

	cin >> in >> k;
	int p = in.size();

	for(int x = 0 ; x < p ; x++){
		int hash = 0;
		int val = 0;
		for(int y = x ; y < min(p, x + 5) ; y++){
			hash = hash * 27 + (in[y] - 'a' + 1);
			val++;
			int now = hash;
			for(int x = 4; x >= val ; x--){
				now = now * 27;
			}
			v.pb(now);
		}
	}
	sort(v.begin(), v.end());

	int siz = v.size();
	int jawab = 0;

	for(int x = 0 ; x < siz; x++){
		if(x == 0){
			k--;
		}else if(v[x] == v[x - 1]){
			continue;
		}else{
			k--;
		}
		if(k == 0){
			jawab = v[x];
			break;
		}
	}

	while(jawab > 0){
		int va = jawab % 27;
		jawab = jawab / 27;
		if(va == 0){
			continue;
		}else{
			ans.pb(va);
		}
	}
	int pp = ans.size();
	for(int x = pp - 1; x >= 0 ; x--){
		printf("%c",ans[x] + 'a' - 1);
	}
	printf("\n");
}	

Submission Info

Judge Result