Kata

An array is called zero-plentiful if it contains multiple zeros, and every sequence of zeros is at least 4 items long.

Your task is to return the number of zero sequences if the given array is zero-plentiful, otherwise 0.

Examples

[0, 0, 0, 0, 0, 1]  -->  1
# 1 group of 5 zeros (>= 4), thus the result is 1

[0, 0, 0, 0, 1, 0, 0, 0, 0]  -->  2
# 2 group of 4 zeros (>= 4), thus the result is 2

[0, 0, 0, 0, 1, 0]  -->  0 
# 1 group of 4 zeros and 1 group of 1 zero (< 4)
# _every_ sequence of zeros must be at least 4 long, thus the result is 0

[0, 0, 0, 1, 0, 0]  -->  0
# 1 group of 3 zeros (< 4) and 1 group of 2 zeros (< 4)

[1, 2, 3, 4, 5]  -->  0
# no zeros

[]  -->  0
# no zeros