【leetcode】按照频率将数组升序排序

 

/**
 * Note: The returned array must be malloced, assume caller calls free().
 */
typedef struct st{
    int val;
    int cnt;
}st;
int cmp(const void* a,const void* b){
    return ((*(st*)a).cnt != (*(st*)b).cnt)?(*(st*)a).cnt-(*(st*)b).cnt :(*(st*)a).val < (*(st*)b).val;
}
int* frequencySort(int* nums, int numsSize, int* returnSize){
    st arr[201]={0};
    int* ret = (int*)calloc(101,sizeof(int));
    int i,pst=0,n=0;
    for(i=0; i<numsSize; ++i){
        arr[nums[i]+100].val=nums[i];     
        arr[nums[i]+100].cnt++;
    }
    qsort(arr,201,sizeof(st),cmp);
    for(i=0; i<201; ++i){
        while(arr[i].cnt){
            ret[pst++]=arr[i].val;
            arr[i].cnt--;
        }
    }
    *returnSize=pst;
    return ret;
}

/**
 * Note: The returned array must be malloced, assume caller calls free().
 */
typedef struct st{
    int val;
    int cnt;
}st;
int cmp(const void* a,const void* b){
    return ((*(st*)a).cnt != (*(st*)b).cnt)?(*(st*)a).cnt-(*(st*)b).cnt :(*(st*)a).val < (*(st*)b).val;
}
int* frequencySort(int* nums, int numsSize, int* returnSize){
    st arr[201]={0};
    int* ret = (int*)calloc(101,sizeof(int));
    int i,pst=0,n=0;
    for(i=0; i<numsSize; ++i){
        arr[nums[i]+100].val=nums[i];     
        arr[nums[i]+100].cnt++;
    }
    qsort(arr,201,sizeof(st),cmp);
    for(i=0; i<201; ++i){
        while(arr[i].cnt){
            ret[pst++]=arr[i].val;
            arr[i].cnt--;
        }
    }
    *returnSize=pst;
    return ret;
}