CF1615B.And It's Non-Zero

You are given an array consisting of all integers from $[l, r]$ inclusive. For example, if $l = 2$ and $r = 5$, the array would be $[2, 3, 4, 5]$. What's the minimum number of elements you can delete to make the bitwise AND of the array non-zero?

A bitwise AND is a binary operation that takes two equal-length binary representations and performs the AND operation on each pair of the corresponding bits.

给你一个包含区间 $[l, r]$ 内所有整数的数组。例如，若 $l = 2$ 且 $r = 5$，则该数组为 $[2, 3, 4, 5]$。你需要删除最少多少个元素，才能使该数组的按位与结果非零？

按位与（bitwise AND）是一种二元运算，它对两个等长的二进制表示逐位执行逻辑与操作。

The first line contains one integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. Then $t$ cases follow.

The first line of each test case contains two integers $l$ and $r$ ($1 \leq l \leq r \leq 2 \cdot 10^5$) — the description of the array.

第一行包含一个整数 $t$（$1 \leq t \leq 10^4$）—— 测试用例的数量。随后是 $t$ 个测试用例。

每个测试用例的第一行包含两个整数 $l$ 和 $r$（$1 \leq l \leq r \leq 2 \cdot 10^5$）—— 描述该数组。

For each test case, output a single integer — the answer to the problem.

对于每个测试用例，输出一个整数——即该问题的答案。

In the first test case, the array is $[1, 2]$. Currently, the bitwise AND is $0$, as $1\ \& \ 2 = 0$. However, after deleting $1$ (or $2$), the array becomes $[2]$ (or $[1]$), and the bitwise AND becomes $2$ (or $1$). This can be proven to be the optimal, so the answer is $1$.

In the second test case, the array is $[2, 3, 4, 5, 6, 7, 8]$. Currently, the bitwise AND is $0$. However, after deleting $4$, $5$, and $8$, the array becomes $[2, 3, 6, 7]$, and the bitwise AND becomes $2$. This can be proven to be the optimal, so the answer is $3$. Note that there may be other ways to delete $3$ elements.

在第一个测试用例中，数组为 $[1, 2]$。当前按位与结果为 $0$，因为 $1\ \& \ 2 = 0$。然而，删除 $1$（或 $2$）后，数组变为 $[2]$（或 $[1]$），此时按位与结果变为 $2$（或 $1$）。可以证明这是最优方案，因此答案为 $1$。

在第二个测试用例中，数组为 $[2, 3, 4, 5, 6, 7, 8]$。当前按位与结果为 $0$。然而，删除 $4$、$5$ 和 $8$ 后，数组变为 $[2, 3, 6, 7]$，此时按位与结果变为 $2$。可以证明这是最优方案，因此答案为 $3$。注意，可能存在其他删除 $3$ 个元素的方式。