How do i create a header file in c promgramming code for classic multiplication algorithm? Please help with a code.

1.1. Classical multiplication algorithm: In positional numeral systems, the natural way of multiplying numbers, known as the classical multiplication algorithm, is by multiplying each digit of the multiplicand by each digit of the multiplier and then adding up all the properly shifted results. This method requires a multiplication table for single digits available to the algorithm. Knuth's classical multiplication algorithm [2] can be stated as shown in Algorithm 1. Algorithm 1 Input: positive integers A-(an,. .-4), having n + 1 base r digits and B-(4-.4), having m + 1 base r digits. Output: the product A-B-(4"nel, . . . ,G), in base r Note: (uv), are two single-precision digits in base r, indicating the result of the addition (1) For 1 from 0 up to m + ,, + 1 do: G 0. (2) For i from 0 up tom do the following: (21) carry 0 (2.2) For j from 0 up to n do the following: (2.2.1) Compute (uv), = G+jt aj . 4 + carry, set G+,- , and carry u. // u and v are Il single-precision IIl digits in baser