Write a C program that can calculate the sum of three equally sized matrices, [A] + [B] + [C]. The input specifications are these:

Read the input from a file with the first line of the file being the number of rows and columns of each matrix. The rest of the file has the elements of the matrices. The output specification is to print the sum matrix. [Hint: Use a function named sum_matrices to accept the 3 matrices and print the sum matrix inside the function]