CF1702D.Not a Cheap String

Let $s$ be a string of lowercase Latin letters. Its price is the sum of the indices of letters (an integer between 1 and 26) that are included in it. For example, the price of the string abca is $1+2+3+1=7$.

The string $w$ and the integer $p$ are given. Remove the minimal number of letters from $w$ so that its price becomes less than or equal to $p$ and print the resulting string. Note that the resulting string may be empty. You can delete arbitrary letters, they do not have to go in a row. If the price of a given string $w$ is less than or equal to $p$, then nothing needs to be deleted and $w$ must be output.

Note that when you delete a letter from $w$, the order of the remaining letters is preserved. For example, if you delete the letter e from the string test, you get tst.

设 $s$ 是一个由小写拉丁字母组成的字符串。其价格定义为字符串中所有字母对应序号（整数，范围为 1 到 26）之和。例如，字符串 abca 的价格为 $1+2+3+1=7$。

给定字符串 $w$ 和整数 $p$。请从 $w$ 中删除最少数量的字母，使得剩余字符串的价格不超过 $p$，并输出该结果字符串。注意：结果字符串可以为空。你可以删除任意位置的字母，不要求这些字母在原字符串中连续。若字符串 $w$ 当前的价格已不超过 $p$，则无需删除任何字母，直接输出 $w$。

注意：从 $w$ 中删除字母后，剩余字母的相对顺序保持不变。例如，若从字符串 test 中删除字母 e，则得到 tst。

The first line of input contains an integer $t$ ($1 \le t \le 10^4$) — the number of test cases in the test. The following are descriptions of $t$ test cases.

Each case consists of two lines.

The first of them is the string $w$, it is non-empty and consists of lowercase Latin letters. Its length does not exceed $2\cdot10^5$.

The second line contains an integer $p$ ($1 \le p \le 5\,200\,000$).

It is guaranteed that the sum of string lengths $w$ over all test cases does not exceed $2 \cdot 10^5$.

输入的第一行包含一个整数 $t$（$1 \le t \le 10^4$）—— 表示测试用例的数量。接下来是 $t$ 个测试用例的描述。

每个测试用例由两行组成。

第一行为字符串 $w$，它非空且仅由小写拉丁字母组成，其长度不超过 $2\cdot10^5$。

第二行为一个整数 $p$（$1 \le p \le 5\,200\,000$）。

保证所有测试用例中字符串 $w$ 的总长度不超过 $2 \cdot 10^5$。

Output exactly $t$ rows, the $i$-th of them should contain the answer to the $i$-th set of input data. Print the longest string that is obtained from $w$ by deleting letters such that its price is less or equal to $p$. If there are several answers, then output any of them.

Note that the empty string — is one of the possible answers. In this case, just output an empty string.

输出恰好 $t$ 行，其中第 $i$ 行应包含第 $i$ 组输入数据的答案。请输出通过对字符串 $w$ 删除若干字母后所能得到的、价格不超过 $p$ 的最长字符串。若存在多个满足条件的答案，则输出任意一个即可。

注意：空字符串也是一种可能的答案，此时只需输出一个空字符串。