How to categorize information inside a C random vector [closed]

I need to make a program in C capable of generate X random numbers(0 to 255), where X is a input from the user. Then the program must Separate the numbers in categories like (0 to 30, 31 to 60, 61 to 90 ... etc) Then i need to print all the categories with the numbers in ascending order and print the frequency of each categorie. So if i have for example in the first category : 32 , 9 ,25 ,211 -> i have to print -> the numbers of this category are: 9,25,32,211 -> The frequency in this category is 4.

The idea behind is make the software randomize a LOT of numbers in order to apply Parallel programmin after for optimization.

I HAVE NO IDEA HOW TO DO THIS Can anyone help?