子串

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
using namespace std;

bool checkExistSubstring(string a, string b){
	if(a.find(b) != string::npos)
		return true;
	else
		return false;
}

string tranmistDecToKth(int n, int k) {
	string sb;
	while (n != 0) {
		if (n % k > 9)
			sb += ((n % k - 10 + 'A'));
		else
			sb += ((n % k) + '0');
		n /= k;
	}
	reverse(sb.begin(), sb.end());
	return sb;
}

string getDifference(int n, string t) {
	for (int k = 2; k <= 16; k++) {
		string str;
		for (int i = 1; i <= n; i++) {
			string s = tranmistDecToKth(i, k);
			str += s;
		}
		if(checkExistSubstring(str, t))
			return "yes";
	}
	return "no";
}

int main() {
	int n;
	string str;
	while (cin >> n && cin >> str)
		cout << getDifference(n, str) << endl;
	return 0;
}

求指教。老是通过率60%（已修正）

import java.util.*;
public class Main {
	public static String getDifference(int n, String t) {
		
		for (int k = 2; k <= 16; k++) {
			StringBuffer res = new StringBuffer();
			for (int i = 1; i <= n; i++) {
				String str = tranmistDecToKth(i, k);
				res.append(str);
			}
			if(checkExistSubstring(res.toString(),t))
				return "yes";
		}
		return "no";
	}
	
	public static boolean checkExistSubstring(String a,String b){
		if(a.indexOf(b) != -1)
			return true;
		else
			return false;
	}
	
	public static String tranmistDecToKth(int n, int k) {
		StringBuffer sb = new StringBuffer();
		while (n != 0) {
			if (n % k > 9)
				sb.append((char) (n % k + 55));
			else
				sb.append(n % k);
			n /= k;
		}
		//System.out.println(sb.reverse().toString());
		return sb.reverse().toString();
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
//		int k = sc.nextInt();
		String s = sc.next();
		String t = sc.nextLine();
		System.out.println(getDifference(n, t));
	}
}