I am trying to fill up the array den and it is giving me java.lang.NullPointerException
Why is that
Thanks
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("Enter an amount:");
float amount= input.nextFloat();
int denom, i=0;
int [] den=null;
do{
System.out.print("Enter denominations: ");
denom=input.nextInt();
den[i]=denom;
i++;
}
while(denom!=0);