二分法查找C++实现

#include 
#include 
using namespace std;

int binary_seacher(vector<int> &v, int target)
{
    if (v.empty())
        return -1;

    int index1 = 0, index2 = v.size() - 1, mid = 0;

    while (index1 <= index2)
    {
        mid = (index1 + index2) / 2;
        if (v[mid] == target)
            return mid;

        if (v[mid] > target)
            index2 = mid-1;
        if (v[mid] < target)
            index1 = mid+1;
    }

    return -1;
}

int main()
{
    int n = 0, target = 0;

    cin >> n >> target;
    vector<int> v(n);

    for (int i = 0; i < n; i++)
    {
        cin >> v[i];
    }

    cout << binary_seacher(v, target);

    system("pause");
    return 0;
}