1313 - Decompress Run-Length Encoded List.

Easy

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). For 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.

Example 1:

Input: nums = 1,2,3,4

Output: 2,4,4,4

Explanation: The first pair 1,2 means we have freq = 1 and val = 2 so we generate the array 2.

The second pair 3,4 means we have freq = 3 and val = 4 so we generate 4,4,4.

At the end the concatenation 2 + 4,4,4 is 2,4,4,4.

Example 2:

Input: nums = 1,1,2,3

Output: 1,3,3

Constraints:

• 2 <= nums.length <= 100

• nums.length % 2 == 0

• 1 <= nums[i] <= 100