Let us now consider operations on numbers that have arbitrarily high precision. For simplicity in exposition, we shall assume that we are working with integers, instead of with numbers that have an embedded radix point.
In this section we shall discuss algorithms for
a) addition or subtraction of n-place integers, giving an n-place answer and a carry;
b) multiplication of an m-place integer by an n-place integer, giving an (m + n)-place answer;
c) division of an (m + n)-place integer by an n-place integer, giving an (m + 1)-place quotient and an n-place remainder.
These may be called the classical algorithms, since the word “algorithm” was used only in connection with these ...