codeforces#P1774A. Add Plus Minus Sign

Add Plus Minus Sign

Description

AquaMoon has a string $a$ consisting of only $0$ and $1$. She wants to add $+$ and $-$ between all pairs of consecutive positions to make the absolute value of the resulting expression as small as possible. Can you help her?

The first line contains a single integer $t$ ($1 \leq t \leq 2\,000$)  – the number of test cases. The description of test cases follows.

The first line of each test case contains a single integer $n$ ($2 \leq n \leq 100$) — the length of $a$.

The second line of each test case contains a string $a$ of length $n$, consisting of only $0$ and $1$.

For each test case, output a string of length $n - 1$ consisting of $-$ and $+$ on a separate line. If there is more than one assignment of signs that produces the smallest possible absolute value, any of them is accepted.

Input

The first line contains a single integer $t$ ($1 \leq t \leq 2\,000$)  – the number of test cases. The description of test cases follows.

The first line of each test case contains a single integer $n$ ($2 \leq n \leq 100$) — the length of $a$.

The second line of each test case contains a string $a$ of length $n$, consisting of only $0$ and $1$.

Output

For each test case, output a string of length $n - 1$ consisting of $-$ and $+$ on a separate line. If there is more than one assignment of signs that produces the smallest possible absolute value, any of them is accepted.

3
2
11
5
01101
5
10001
-
+-++
+++-

Note

In the first test case, we can get the expression $1 - 1 = 0$, with absolute value $0$.

In the second test case, we can get the expression $0 + 1 - 1 + 0 + 1 = 1$, with absolute value $1$.

In the third test case, we can get the expression $1 + 0 + 0 + 0 - 1 = 0$, with absolute value $0$.