Fast Fourier Transform, Algorithms, Pattern Matching, Convolution, Combination Sum.
1 result = 0 for i in range(len(new_coefficients)): result += new_coefficients[i]*h h *= 10 return result if sign else -result p, q = 1234, 6789 assert multiply(p, q) == p*q Huh !!! all those codes for just doing simple multiplication. The time complexity for the above code is clearly O(n²). So how