Score : 500 points
You are given a sequence with N integers: A = \{ A_1, A_2, \cdots, A_N \}. For each of these N integers, we will choose a color and paint the integer with that color. Here the following condition must be satisfied:
Find the minimum number of colors required to satisfy the condition.
Input is given from Standard Input in the following format:
N A_1 : A_N
Print the minimum number of colors required to satisfy the condition.
5 2 1 4 5 3
2
We can satisfy the condition with two colors by, for example, painting 2 and 3 red and painting 1, 4, and 5 blue.
4 0 0 0 0
4
We have to paint all the integers with distinct colors.