有序数组
int GetNumberSameAdIndex(vector<int>number)
{
if (number.size() == 0)return -1;
int L = 0, R = number.size() - 1;
while (L <= R)
{
int middle = (R - L) / 2 + L;
if (number[middle] == middle)return middle;
if (number[middle] > middle)R = middle - 1;
else L = middle + 1;//如果等于前面已经跳出了
}
if (L == number.size()-1)return L;
return -1;
}
