Nearest Beautiful Number (easy version)

题意翻译

给定数据组数 $t$，每组数据包含正整数 $n$、$k$，求满足 $x\geq n$ 的最小正整数 $x$，使 $x$ 是个 $k$-beautiful 数。 一个正整数是个 $k$-beautiful 数，当且仅当其无前导零的十进制数值表示中，不同的数字不超过 $k$ 个。 数据满足 $1 \leq t \leq 10^4$，$1 \leq n \leq 10^9$，$1 \leq k \leq 2$。

题目描述

It is a simplified version of problem F2. The difference between them is the constraints (F1: $ k \le 2 $ , F2: $ k \le 10 $ ). You are given an integer $ n $ . Find the minimum integer $ x $ such that $ x \ge 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.

输入输出格式

输入格式

The first line contains one integer $ t $ ( $ 1 \le t \le 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 \le n \le 10^9 $ , $ 1 \le k \le 2 $ ).

输出格式

For each test case output on a separate line $ x $ — the minimum $ k $ -beautiful integer such that $ x \ge n $ .

输入输出样例

输入样例 #1

4
1 1
221 2
177890 2
998244353 1

输出样例 #1

1
221
181111
999999999