#include<iostream>
using namespace std ;

int main(){
	
	int n , k , zero , one ;
	
	while(1){
		cin >> n ;
		if( n==0 ) break;
		
		zero = 0 ;
		one = 0 ;
		for( int i=0 ; i<n ; i++ ){
			cin >> k ;
			if( k == 0 ) zero++ ;
			if( k == 1 ) one++ ;
		}
		
		if( zero + one == n ) cout << "NA" << endl ;
		else cout << n - zero +1 << endl ;
	}
	
return 0; 
}