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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | /** * Note: The returned array must be malloced, assume caller calls free(). */ int* decompressRLElist(int* nums, int numsSize, int* returnSize){ *returnSize = 0; for(int i=0;i<numsSize;i+=2){ *returnSize += nums[i]; } int* ret = (int*)malloc(sizeof(int)**returnSize); int index = 0; for(int i=0;i<numsSize;i+=2){ for(int j=0;j<nums[i];++j){ ret[index+j]=nums[i+1]; } index += nums[i]; } return ret; } |