Testcases not passed . Kindly provide some hints

#1

2 testcases did not pass . Kindly help in corner cases

#2

// Chewbacca and Numbers

// given a number invert its digits (9-t) and find smallest number

#include
#include
using namespace std;
int main(){
long long N ;
cin>>N;

// Exception if number is 0 then dont do anything
if(N == 0 )
{
	cout<<N;
	return 0 ;
}

// store the number in an array in reverse order
vector<int> arr;
while(N>0){
	arr.push_back(N%10);
	N= N/10 ;
}
int len = arr.size();

// Check at each index to find minimum value and Replace 
for (int i = 0 ;i<len;i++){
	
	if(arr[i] > (9 - arr[i])){
		arr[i] = (9 - arr[i]);
	}
}

// Make the ans by forming the new Number 
long long ans = 0 ;
for(int i = len-1 ; i >=0 ;i--){
	ans = ans*10 + arr[i];
}

cout<<ans ;

}

#3

hey @achin1tya in the case where the first digit is nine for example 9444 you are making 9 zero, but it is mentioned in the question that number shouldnt start with zero so you should include an exception that if the first character is 9, do not change it.

#4

thx man . I totally forgot about this case.