#include<bits/stdc++.h>
using namespace std;
int n,m,k,t,a[1000005],s[100005];
int erfen(int n,int key){
	int l=1,r=n,ans=-1;
	while(l<=r){
		int mid=(l+r)/2;
		if(a[mid]==key){
			l=mid+1;
		}
		else if(a[mid]<key){
			l=mid+1;
		}
		else{
			r=mid-1;
			ans=mid;
		}
		mid=(l+r)/2;
	}
	return ans;
}
int main(){
	cin>>n>>m;
	for(int i=1;i<=n;i++)cin>>a[i];
	cout<<erfen(n,m);
	return 0;
}

#include<bits/stdc++.h> using namespace std; int main(){ int n,k,i; cin>>n>>k; int a[200005]; for(i=0;i<n;i++)cin>>a[i]; int l=0,r=n-1,ans=-1; while(l<=r){ int mid=(l+r)/2; if(a[mid]>k){ ans=mid+1; r=mid-1; }else l=mid+1; } cout<<ans; return 0; }

#include<bits/stdc++.h> using namespace std; int main(){ int n,k,i; cin>>n>>k; int a[200005]; for(i=0;i<n;i++)cin>>a[i]; int l=0,r=n-1,ans=-1; while(l<=r){ int mid=(l+r)/2; if(a[mid]>k){ ans=mid+1; r=mid-1; }else l=mid+1; } cout<<ans; return 0; }