Description

There are two octal integers numbers $a$ and $b$.You need to calculate the result of $a$ minus $b$，then output in octal notation.

If the result is negative, you should use the negative sign instead of complement notation.

Format

Input

The first line is an integer $T(1 \leq T \leq 1000)$, indicating the number of test cases.

For each case, the first and only line contains two octal integers $a, b. (0 \leq a, b < 2^{100})$.

Output

Print the result contains a list of the fully qualified octal digits，one per line.

Samples

1
76 7

67