Mean equals Median

Chef gets confused between mean and median very often, and as a result, he has developed a dislike of arrays whose mean and median are not equal. Chef has an array $A$ of $N$ elements. He can perform the following operation on it: - Pick an index $1 \leq i \leq N$ and increase $A_i$ by $1$. He would like to obtain an array whose mean and median are equal. Determine the **minimum** number of oper