description: It is a simplified version of problem F2. The difference between them is the constraints (F1: k ≤ 2, F2: k ≤ 10).
  
  You are given an integer n. Find the minimum integer x such that x ≥ n and the number x is k-beautiful.
  
  A number is called k-beautiful if its decimal representation having no leading zeroes contains no more than k different digits. E.g. if k = 2, the numbers 3434443, 55550, 777 and 21 are k-beautiful whereas the numbers 120, 445435 and 998244353 are not.
  
  Input
  
  The first line contains one integer t (1 ≤ t ≤ 10^4) — the number of test cases. Then t test cases follow.
  
  Each test case consists of one line containing two integers n and k (1 ≤ n ≤ 10^9, 1 ≤ k ≤ 2).
  
  Output
  
  For each test case output on a separate line x — the minimum k-beautiful integer such that x ≥ n.
  
  Example
  
  Input
  
  
  4
  1 1
  221 2
  177890 2
  998244353 1
  
  
  Output
  
  
  1
  221
  181111
  999999999
solution: import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.StringTokenizer;
  import java.util.TreeSet;
  
  public class C2 {
  	static TreeSet<Long> set1;
  	static TreeSet<Long> set2;
  
  	private static void sport(int n, int k) {
  		if (k == 1) {
  			Long ceiling = set1.ceiling((long) n);
  			System.out.println(ceiling);
  		} else {
  			Long ceiling = set2.ceiling((long) n);
  			System.out.println(ceiling);
  		}
  	}
  
  	static void generate(int a, int b, int cnt, long val, TreeSet<Long> set) {
  		if (cnt > 11) {
  			return;
  		}
  		set.add(val);
  		generate(a, b, cnt + 1, val * 10 + a, set);
  		generate(a, b, cnt + 1, val * 10 + b, set);
  	}
  
  	static void precalc() {
  		for (int i = 0; i < 10; i++) {
  			generate(i, i, 0, 0, set1);
  		}
  		for (int i = 0; i < 10; i++) {
  			for (int j = i; j < 10; j++) {
  				generate(i, j, 0, 0, set2);
  			}
  		}
  	}
  
  	public static void main(String[] args) {
  		FastScanner sc = new FastScanner();
  		set1 = new TreeSet<>();
  		set2 = new TreeSet<>();
  		precalc();
  		int t = sc.nextInt();
  		for (int i = 0; i < t; i++) {
  			int n = sc.nextInt();
  			int k = sc.nextInt();
  			sport(n, k);
  		}
  	}
  
  	static class FastScanner {
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer st = new StringTokenizer("");
  
  		String next() {
  			while (!st.hasMoreTokens()) {
  				try {
  					st = new StringTokenizer(br.readLine());
  				}
  				catch (IOException e) {
  					e.printStackTrace();
  				}
  			}
  			return st.nextToken();
  		}
  
  		int nextInt() {
  			return Integer.parseInt(next());
  		}
  
  		long[] readArrayLong(int n) {
  			long[] a = new long[n];
  			for (int i = 0; i < n; i++) {
  				a[i] = nextLong();
  			}
  			return a;
  		}
  
  		int[] readArrayInt(int n) {
  			int[] a = new int[n];
  			for (int i = 0; i < n; i++) {
  				a[i] = nextInt();
  			}
  			return a;
  		}
  
  		long nextLong() {
  			return Long.parseLong(next());
  		}
  
  		double nextDouble() {
  			return Double.parseDouble(next());
  		}
  	}
  }