from collections import counterdef count_pairs: m = int(input) a = list(map(int, input.split)) n = int(input) b = list(map(int, input.split)) count_a = Counter(a) count_b = Counter(b) result = 0 for num in count_a: if num in count_b: result += count_a[num] * count_b[num] print(result)count_pairs摘要：from collections import counterdef count_pairs: m = int(input) a = list(map(int, input.split)) n = int(input) b = list(map(int, in
来源：晓啸教育
