Minimum number of Flips

Chef has an array $A$ of length $N$ consisting of $1$ and $-1$ only. In one operation, Chef can choose any index $i$ $(1\le i \le N)$ and multiply the element $A_i$ by $-1$. Find the **minimum** number of operations required to make the sum of the array equal to $0$. Output `-1` if the sum of the array cannot be made $0$. ### Input - First line will contain $T$, number of test cases. Then the t