题目描述
A = [A1, A2, … AN],
B = [B1, B2, … BN],
C = [C1, C2, … CN],
请你统计有多少个三元组(i, j, k) 满足:
1. 1 <= i, j, k <= N
2. Ai < Bj < Ck
输入格式
输出格式
样例输入
3 1 1 1 2 2 2 3 3 3
样例输出
27
比赛公告
2018年真题精选
2194,2276,2277,2279,2280,2281,2282,2283,2284,2285,2286,2287,
2288,2291,2292,2294,2296
2194,2276,2277,2279,2280,2281,2282,2283,2284,2285,2286,2287,
2288,2291,2292,2294,2296