m,n = map(int,input().split()) list1 = [] for _ in range(m): row = list(map(int, input().split())) list1.append(row) list2 = [] for _ in range(m): row = list(map(int, input().split())) list2.append(row) yiy = 0 a = m * n for i in range(m): for j in range(n): if list1[i][j] == list2[i][j]: yiy += 1 bl = (yiy/a) * 100 print("{0:.2f}".format(bl))