Median in Rotated Array

/***
find median of rotated sorted array.
O(logn)
***/

#include<iostream>
using namespace std;

int find_start(int *a, int st, int ed) {
       if(st >= ed) return st;

       int mid = (st + ed) / 2;

       if(a[mid] < a[mid-1]) return mid;

       if(a[mid] > a[ed]) {
              return find_start(a, mid+1, ed);
       } else {
              return find_start(a, st, mid-1);
       }
}

int get_median(int *a, int sz) {
       int m = sz/2;
       int id = find_start(a, 0, sz-1);
       cout<<"index:"<<id<<endl;
       if(sz%2) {          
              if(id + m < sz)
                     return a[id+m];
              else return a[m+id-sz];
       } else {
              if(id+m < sz)
                     return (a[id+m]+a[id+m-1])/2;
              else if(id+m == sz)
                     return (a[0] + a[id+m-1])/2;
              else return (a[m+id-sz] + a[m+id-sz-1])/2;
       }
}

void main() {
       int a[] = {1, 2, 3, 4, 5, 6, 7};
       int sz = sizeof(a) / sizeof(int);

       cout<<get_median(a, sz)<<endl;

}

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