check for edge cases
given sample inputs usually are simple
5-stars aap par bohot badhiya lag rahe hai.Congratulations 
couldn’t find any…please help
There is issue with your code.
Error 1 : You have mistake in taking input
Given the limit of N is (1 <= “N” <= 1000)
This means in next line you can have a string with 1000 characters (i.e 1000000000…0000000…0000) , but you have declared a variable “r” as long which cannot hold the value as max value of long is 2147483648 i.t around 10 digits .
I hope you understood the issue.
int n=Integer.parseInt(br.readLine());
**long r=Long.parseLong(br.readLine());**
long a[]=new long[n];
for(int i=n-1;i>=0;i--)
{
a[i]=r%10;
r=r/10;
}
You can use something like this. Take a string as input then feed the same into array.
String s=br.readLine();
String[] strs = s.trim().split("");
int a[]=new int[strs.length];
int l=strs.length;
for (int i = 0; i <l ; i++) {
a[i] = Integer.parseInt(strs[i]);
}
Error 2 : You also missed an edge case when n==1 , Your program fails
int count=0;
if(n==1){
if(a[0]==0)
count++;
}else{
//Your code logic to increment count
}
Happy to Help 3000 . 