Polynomial Multiplication is a very necessary thing in mathematics and engineering. Finding ways to solve this problem in low time complexity is a big goal. A naive approach can fetch you a O(n^2) algorithm. With FFT we can scale this down to O(nlogn) using Divide and Conquer strategy applied on Discrete Fourier Transform(DFT).
- MIT OCW - MIT-OCW FFT Lecture by Eric Demaine
- CP-Algorithm - cpalgorithm