Yet Another Easy Problem

You are given an array $A$ of $N$ positive integers. In one step you should choose an index $i$ ($0 \leq i \leq N - 1$) with the largest positive number in the array (if there are several indices choose any) and reduce $A_i$ by 1. You should repeat this until the array contains no positive integer. Figure out if this is possible in such a way that you **don't choose the same $i$ twice in a row**.