C programming only

Write a program that will compute the factorial of a number supplied by the user. In math, x! is the product of all whole numbers starting with 1 and continuing up to x (assuming x is a positive number).it is termed "x factorial". Your program should: prompt a user to enter a positive number(datatype int) that they'd like to calculate the factorial for. you should use a while loop to make sure that the user enters a positive number(not zero) and make them enter a new value until their input is valid using a for loop, calculate the factorial of the valid number entered by the user Output the value of the factorial of the number Test your program with 15