CentralNotice From Wikipedia, the free encyclopedia Jump to: navigation , search A multiplication algorithm is an algorithm (or method) to multiply two numbers. Depending on the size of the numbers, different algorithms are in use. Efficient multiplication algorithms have existed since the advent of the decimal system. 1 Grid method 2 Long multiplication 2.1 Example 2.2 Space complexity 2.3 Electronic usage 3 Lattice multiplication 3.1 Example 4 Peasant or binary multiplication 4.1 Examples 5 Shift and add 6 Quarter square multiplication 7 Algorithm for multiplying numbers close to a round number 8 Fast multiplication algorithms for large inputs 8.1 Gauss's complex multiplication algorithm 8.2 Karatsuba multiplication 8.3 Toom–Cook 8.4 Fourier transform methods 9 Lower bounds 10 Polynomial multiplication 11 See also 12 References 13 Ex...