a$.$ write a sequential C program to compare two integer N x N arrays and report how many elements are different $($i$.$e$.$ if A$[$i$][$j$]$ is different to B$[$i$][$j$],$ for all i and j$)$ with a print statement. N is a defined constant set to $1000.$ assume the arrays are initialized.

b$.$ Modify the code using OpenMP directives to parallelize the code using P threads, where P is also a defined constant and N is a multiple of P$.$

c$.$ Finally re$-$write the code to be an MPI program with P processes.

Keep code simple and comment and explain each and every line of code.