My hash has 3 fields

f1 = size of interval

f2 = sum of array elements over interval(a[i] +a[i+1]...a[j])

f2 = sum of squares of array elements over interval(a[i]^2 + a[i+1]^2 .. a[j]^2).

if all 3 matches, then elements are indeed same. Can this be broken?

P.S. While in attempt to solve D from previous contest(https://codeforces.me/contest/1284/problem/D). I was looking for this question.