LeetCode 35. Search Insert Position

Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.

You may assume no duplicates in the array.

Here are few examples.
[1,3,5,6], 5 → 2
[1,3,5,6], 2 → 1
[1,3,5,6], 7 → 4
[1,3,5,6], 0 → 0

// Need to pay attention to the third example. nums.size() is included.

#include <vector>
#include <iostream>
using namespace std;

int searchIndex(vector<int>& nums, int target) {
    if(nums.size() == 1) return 0;
    int left = 0, right = nums.size();  // pay attention here!
    while(left < right) {
        int mid = (left + right) / 2;
        if(nums[mid] >= target) right = mid;
        else left = mid + 1;
    }
    return left;
}

int main(void) {
    vector<int> nums{1, 3, 5, 6};
    int pos = searchIndex(nums, 7);
    cout << pos << endl;
}