The is sorted function does not work correctly in my code

so bacicly i have this code in which you cin a number and then an array of this number size example

6

2

4

7

7

9

3

all of them being in an index i of the array like this

2-----0

4-----1

7-----2

7-----3

9-----4

3-----5

so in this code what i want to find if all the elements from index 3 to the end are sorted

if 7 9 3 is sorted using the is sorted funtion like this

is_sorted(v+2+1,v+n-2-1)

so this would be like is_sorted(0+2+1,0+6-2-1)

or is_sorted(3,3)

so it should chek if the 3 elements from index 3 are sorted

bacicly checking if the array 7 9 3 is sorted which is obviosly not true but my code throws 1 instead of 0

 #include <bits/stdc++.h>
    using namespace std;
    int main() {
    int n;

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



    cout<<is_sorted(v+2+1,v+n-2-1);


     return 0;
    }