"""
We are given a list nums of integers representing a 
list compressed with run-length encoding.

Consider each adjacent pair of elements 
[freq, val] = [nums[2*i], nums[2*i+1]] (with i >= 0).  
or each such pair, there are freq elements
with value val concatenated in a sublist.
Concatenate all the sublists from left to right to 
generate the decompressed list.

Return the decompressed list.
"""

nums = [1,2,3,4]
count = []

for i in range(0, len(nums), 2):
    for j in range(0, nums[i]):
        count.append(nums[i+1])

print(count)
