find pivot in an array

#include<iostream>
using namespace std;

int getPivot(int arr[], int size){
    int s = 0;
    int e = size -1;
    int mid = s+(e-s)/2;

    while(s<e){
        if(arr[mid] >= arr[0]){
            s = mid+1;
        }
        else{
            e = mid;
        }
         mid = s+(e-s)/2;

    }
    return s;
}

int main(){

    int arr[5] = {3,8,10,17,1};
    cout << "pivot element index is " << getPivot(arr , 5) << endl;
}