Minimum Colours (Easy)

**This is the easy version of the problem. The difference is that you remember all array elements correctly, and there is no $A_i = 0$. It is worth 40 points in Division 2, 3 and 4. It is non-scoreable in Division 1.** You have an array $A$ of $N$ integers - $A_1, A_2, ..., A_N$. You can perform the following operation as many times as you want: - Choose $L, R$ such that $1 \le L < R \le N$ and