[C++知识库]【无标题】找出两数组的不同

/**
 * Return an array of arrays of size *returnSize.
 * The sizes of the arrays are returned as *returnColumnSizes array.
 * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().
 */
int** findDifference(int* nums1, int nums1Size, int* nums2, int nums2Size, int* returnSize, int** returnColumnSizes){
    int r1,r2,i,j;
    int temp;
    r1 = 0;
    r2 = 0;
    int **a = (int **)malloc(sizeof(int *) * 2);
    a[0] = (int *)malloc(nums1Size * sizeof(int));
    a[1] = (int *)malloc(nums2Size * sizeof(int));
    *returnColumnSizes = (int *)malloc(2 * sizeof(int));
    
    for(i = 0; i < nums1Size; i++){
        for(j = 0; j < nums1Size; j++){
            if(nums1[i] == nums1[j] && i != j){
                nums1[j] = 1001;
            }
        }
    }    
      for(i = 0; i < nums2Size; i++){
        for(j = 0; j < nums2Size; j++){
            if(nums2[i] == nums2[j] && i != j){
                nums2[j] = 1001;
            }
        }
    } 
    for(i = 0; i < nums1Size; i++){
        temp = nums1[i];
        for(j = 0; j < nums2Size; j++){
            if(temp == nums2[j]){
                nums1[i] = 1001;
                nums2[j] = 1001;
            }
        }
    }
    
    i = 0;
    j = 0;
    while(i < nums1Size){
        if(nums1[i] != 1001){
            a[0][j++] = nums1[i++];
            r1++;
        } else {
            i++;
        }
    }
    
    i = 0;
    j = 0;
     while(i < nums2Size){
        if(nums2[i] != 1001){
            a[1][j++] = nums2[i++];
            r2++;
        } else {
            i++;
        }
    }
    (*returnColumnSizes)[0] = r1;
    (*returnColumnSizes)[1] = r2;
    *returnSize = 2;
    return a;
}