## 1313. Decompress Run-Length Encoded List

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 .
The second pair [3,4] means we have freq = 3 and val = 4 so we generate [4,4,4].
At the end the concatenation  + [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`

## Rust Solution

``````struct Solution;

impl Solution {
fn decompress_rl_elist(nums: Vec<i32>) -> Vec<i32> {
let mut res = vec![];
for p in nums.chunks(2) {
let a = p as usize;
let b = p;
for _ in 0..a {
res.push(b);
}
}
res
}
}

#[test]
fn test() {
let nums = vec![1, 2, 3, 4];
let res = vec![2, 4, 4, 4];
assert_eq!(Solution::decompress_rl_elist(nums), res);
}
``````

Having problems with this solution? Click here to submit an issue on github.