Frequencias.java

How many times a specific number appears in a list of n numbers at the input.
For example:  input = 1,2,3,1,2,1.
How many times does the number 1 appear?
R: 3 times.
How many times does the number 2 appear?
R: 2 times.
How many times does the number 3 appear?
R: once.