//找到开始位置下标
int leftRange(int *nums,int numsSize,int target)
{
    int left = 0;
    int right = numsSize - 1;
    int range;
    while(left <= right)
    {
        int mid = (right - left) / 2 + left;  //防止加法发生整形溢出
        if(nums[mid] >= target)   //只要mid的左边有target元素，就向左检索
        {
            right = mid - 1;
            range = right;    //存储可能成为开始位置的下标
        }
        else
            left = mid + 1;
    }
    return range+1;   //最后一次right=mid-1使得left>right，可以认为这是一个无效运算，因此需要将-1抵消
}    
//找到结束位置下标
int rightRange(int *nums,int numsSize,int target)
{
    int left = 0;
    int right = numsSize - 1;
    int range;
    while(left <= right)
    {
        int mid = (right - left) / 2 + left;
        if(nums[mid] > target)
            right = mid - 1;
        else    //只要mid的右边有target元素，就向右检索
        {
            left = mid + 1;  
            range = left;
        }
    }
    return range-1; //最后一次left=mid+1使得left>right，可以认为这是一个无效运算，因此需要将1抵消
}
int* searchRange(int* nums, int numsSize, int target, int* returnSize){
    *returnSize = 2;
    int *number = (int *)malloc(sizeof(int) * (*returnSize));
    int left = 0;
    int right = numsSize - 1;
    int flag = 0;
    while(left <= right)    //首先判断target是否存在于数组中
    {
        int mid = (right - left) / 2 + left;
        if(nums[mid] < target)
            left = mid + 1;
        else if(nums[mid] > target)
            right = mid - 1;
        else
        {
            flag = 1;
            break;
        }
    }
    if(flag)  //如果存在
    {
        number[0] = leftRange(nums,numsSize,target);
        number[1] = rightRange(nums,numsSize,target);
    }
    else  //如果不存在
        number[0] = number[1] = -1;
    return number;
}