Didn't get very far with hw5

OSU Coursework/CS 325 - Analysis of Algorithms/HW 5/hw5.py

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+from time import time
+from random import randint
+
+
+def generate_polynomials(k_input):
+    n = 2 ** k_input
+
+    left = [randint(0, 10) for _ in range(n)]
+    right = [randint(0, 10) for _ in range(n)]
+
+    return left, right
+
+
+def iterative_poly_solver(left_coefficients, right_coefficients):
+    result_coefficients = [0 for _ in range(len(left_coefficients) + len(right_coefficients) - 1)]
+
+    for left_index, left_val in enumerate(left_coefficients):
+        for right_index, right_val in enumerate(right_coefficients):
+            result_coefficients[left_index + right_index] = left_val * right_val + result_coefficients[left_index + right_index]
+    return result_coefficients
+
+
+def recursive_poly_solver(left_coefficients, right_coefficients):
+    if len(left_coefficients) == 1 and len(right_coefficients) == 1:
+        return [left_coefficients[0] * right_coefficients[0]]
+
+    halfway = len(left_coefficients) // 2
+
+    left_lower_half = left_coefficients[:halfway]
+    left_higher_half = left_coefficients[halfway:]
+
+    right_lower_half = right_coefficients[:halfway]
+    right_higher_half = right_coefficients[halfway:]
+
+    sum_low_high_left = [0 for _ in range(len(left_lower_half))]
+    sum_low_high_right = [0 for _ in range(len(right_lower_half))]
+
+    for i in range(len(left_lower_half)):
+        sum_low_high_left[i] = left_lower_half[i] + left_higher_half[i]
+        sum_low_high_right[i] = right_lower_half[i] + right_lower_half[i]
+
+    low_left_low_right_multiply = recursive_poly_solver(left_lower_half, right_lower_half)
+    sums_multiple = recursive_poly_solver(sum_low_high_left, sum_low_high_right)
+    high_left_high_right_multiply = recursive_poly_solver(left_higher_half, right_higher_half)
+
+    combined = [0 for _ in range(len(left_coefficients) + len(right_coefficients) - 1)]
+
+    for i in range(len(left_coefficients) - 1):
+        combined[i] += low_left_low_right_multiply[i]
+        combined[i + halfway] += sums_multiple[i] - low_left_low_right_multiply[i] - high_left_high_right_multiply[i]
+        combined[i + 2 * halfway] += high_left_high_right_multiply[i]
+
+    return combined
+
+
+if __name__ == '__main__':
+    for i in range(20):
+        left, right = generate_polynomials(i)
+
+        start = time()
+        iterative_poly_solver(left, right)
+        print("%s\t%s" % (2 ** i, time()-start))
+
+    # for i in range(10):
+    #     left, right = generate_polynomials(i)
+    #         print(recursive_poly_solver(left[0], right[1]))