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#7585. TDL

Statistiques

对于正整数 $n$,记 $f(n, m)$ 为满足 $x > n$ 且 $\gcd(x, n) = 1$ 的第 $m$ 小的整数 $x$。例如,$f(5, 1) = 6$ 且 $f(5, 5) = 11$。

给定 $m$ 和 $k = (f(n, m) - n) \oplus n$ 的值,其中 “$\oplus$” 表示按位异或运算。请编写一个程序,求出满足 $(f(n, m) - n) \oplus n = k$ 的最小正整数 $n$,若不存在则输出 -1。

输入格式

第一行包含一个整数 $T$ ($1 \le T \le 10$),表示测试用例的数量。 每个测试用例由一行组成,包含两个整数 $k$ 和 $m$ ($1 \le k \le 10^{18}, 1 \le m \le 100$)。

输出格式

对于每个测试用例,输出一行,包含一个整数:满足条件的最小 $n$。如果无解,则输出 “-1”。

样例

输入 1

2
3 5
6 100

输出 1

5
-1

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