Sublists

You are given a list containing $n$ integers. Your task is to count how many sublists have the sum $0$ and additionally have the same first and last number.

The time complexity of the algorithm should be $O(n)$.

In a file sublists.py, implement a function count that returns the number of sublists.

def count(t):
    # TODO

if __name__ == "__main__":
    print(count([2,3,-7,2])) # 1
    print(count([1,2,3,4,5])) # 0
    print(count([0,0,0,0,0])) # 15
    print(count([2,1,-2,1,-1,1,-1,1])) # 3

Explanation: In the last test, the sublists are $[1,-2,1]$, $[1,-2,1,-1,1]$ and $[1,-2,1,-1,1,-1,1]$.