CF2074C.XOR and Triangle

传统题 时间 2000 ms 内存 256 MiB 5 尝试 1 已通过 1 标签

XOR and Triangle

This time, the pink soldiers have given you an integer xx (x≥2x \ge 2).

Please determine if there exists a positive integer yy that satisfies the following conditions.

  • yy is strictly less than xx.
  • There exists a non-degenerate triangle∗^{\text{∗}} with side lengths xx, yy, x⊕yx \oplus y. Here, ⊕\oplus denotes the bitwise XOR operation.

Additionally, if there exists such an integer yy, output any.

∗^{\text{∗}}A triangle with side lengths aa, bb, cc is non-degenerate when a+b>ca+b \gt c, a+c>ba+c \gt b, b+c>ab+c \gt a.

Input

Each test contains multiple test cases. The first line contains the number of test cases tt (1≤t≤20001 \le t \le 2000). The description of the test cases follows.

The only line of each test case contains a single integer xx (2≤x≤1092 \le x \le 10^9).

Output

For each test case, print one integer on a separate line. The integer you must output is as follows:

  • If there exists an integer yy satisfying the conditions, output the value of yy (1≤y<x1 \le y \lt x);
  • Otherwise, output −1-1.

If there exist multiple integers that satisfy the conditions, you may output any.

Note

In the first test case, there exists a non-degenerate triangle with side lengths 33, 55, and 3⊕5=63 \oplus 5 = 6. Therefore, y=3y=3 is a valid answer.

In the second test case, 11 is the only possible candidate for yy, but it cannot make a non-degenerate triangle. Therefore, the answer is −1-1.

Samples

7
5
2
6
3
69
4
420
3
-1
5
-1
66
-1
320

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