PICKING PERFECT TRIO

[sirdan]

Solve PICKING PERFECT TRIO

i am unable to implement it.
what data structure is best??

[sameer_bamanha]

This is the same problem i guess:
Problem:

COUNTARI Problem - CodeChef

Editorial:

COUNTARI - Editorial

PROBLEM LINK Practice Contest DIFFICULTY HARD PREREQUISITES Dynamic Programming, Discrete Fourier Transform, Fast Fourier Transform PROBLEM You are given a list of integers between 1 and 30000, inclusive. You have to find triplets i < j < k in A[], such that A[i], A[j] and A[k] are in Arithmetic Progression. QUICK EXPLANATION The trivial algorithm to solve this problem is O(N3). This is of course too slow for N = 100,000. Let us consider the O(N2) algorithm below to solve this problem. It …

[sirdan]

Wow ,its the same problem. Thank you so much