C solution using qsort
\n// Let it be global to be used in cmp(). \nint count[201];\n\nint cmp(const void *a, const void *b){\n    if(count[*(int*)a + 100] != count[*(int*)b + 100])\n
```\n// Let it be global to be used in cmp(). \nint count[201];\n\nint cmp(const void *a, const void *b){\n    if(count[*(int*)a + 100] != count[*(int*)b + 100])\n        return count[*(int*)a + 100] > count[*(int*)b + 100];\n    else\n        return *(int*)a < *(int*)b;\n}\n\nint* frequencySort(int* nums, int numsSize, int* returnSize){\n    int i, l = numsSize;\n    memset(count, 0, sizeof(count));\n    \n    for(i = 0; i < l; i++){\n        count[nums[i] + 100]++;\n    }\n    \n    qsort(nums, l, sizeof(int), cmp);\n    *returnSize = l;\n    \n    return nums;\n}\n```
['C']