Pls Help me! How to built this program in 'C'?

[kunal]

Write an interactive program that reads three (3) lists of numbers, which are stored in three separate files, and creates one (1) sorted list. Each file should contain not more than 15 numbers. First, you need to create a program that randomly chooses a size (<= 15 numbers) for the list1 and then randomly generates a list of numbers and store them in the file1. Repeat this procedure to select the other two lists (list2 and list3) and stores them in the corresponding files (file2 and file3) for sorting and merging them into one.

file1(list 1) 32 12 5 990 1
file2 (list 2) 2000 3
file3 (list 3) 30 6
Output in a separate file:
1 3 5 6 12 30 32 990 2000

[WingedPanther]

It sounds like there are several tasks involved in this project. Have you identified the tasks involved and attempted any of them yet? If so, where are you having a problem?