[1630] Arithmetic Subarrays

江湖上傳說memcpy 很慢

嗯......為什麼呢 XD！？

另一種寫法不需要sorting，但是用C的角度來看～覺得沒有比較快(?)

C沒有 find 這種東西啊！！！（怒吼）

/**

* Note: The returned array must be malloced, assume caller calls free().

*/

int comp(const void *a, const void *b)

{

return ( *(int *)a - *(int *)b);

}

bool* checkArithmeticSubarrays(int* nums, int numsSize, int* l, int lSize, int* r, int rSize, int* returnSize) {

*returnSize = lSize;

bool *ret = calloc (lSize, sizeof(bool));

for (int i=0; i<lSize; i++)

{

int len = r[i]-l[i]+1;

int *arr = calloc (len, sizeof(int));

int idx = l[i];

#if 0

memcpy(arr, nums+idx, sizeof(int)*len);

#else

for (int k=0; k<len; k++)

arr[k]= nums[idx+k];

#endif

qsort((void *)arr,len,sizeof(int),comp);

ret[i]= true;

int diff = arr[1]-arr[0];

for (int j=1; j<len-1; j++)

{

if (arr[j+1]-arr[j] != diff)

{

ret[i]= false;

break;

}

}

}

return ret;

}