2018-01-22 A+B Problem 16年香港网络赛 FFT
鉴于这个题目所在的OJ不太好找, 故这里直接附上传送门:https://open.kattis.com/problems/aplusb题目描述:Given N integers in the range [−50000,50000], how many ways are there to pick three integers ai,aj,ak, such that i,j
