Lukuvälit

import java.util.Scanner;
import java.util.ArrayList;
import java.util.List;

class lukuvalit{
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int n = Integer.parseInt(input.nextLine());
        
        List<String[]> numPairs = new ArrayList<String[]>();

        for(int i = 0; i<n; i++){
            String numbers = input.nextLine();
            String[] nums = numbers.split(" ");
            numPairs.add(nums);
        }
        input.close();
        
        for(String[] ab : numPairs){
            long a = Long.parseLong(ab[0]);
            long b = Long.parseLong(ab[1]);

            if(a == b){
                if(isValid(Long.toString(a))){
                    System.out.println(1);
                }else{
                    System.out.println(0);
                }
            }else{
                int output = 0;
                if(a == 0){
                    a+=1;
                    output += 1;
                }
                long first = -1L;
                long last = -1L;

                for(long i = a; i <= b; i++){
                    if(isValid(Long.toString(i))){
                        first = i;
                        break;
                    }
                }

                for(long i = b; i>=a; i--){
                    if(isValid(Long.toString(i))){
                        last = i;
                        break;
                    }
                }

                if(first != -1 && last != -1){
                    int startBinaryVal = getBinary(Long.toString(first));
                    int endBinaryVal = getBinary(Long.toString(last));

                    int val = (endBinaryVal-startBinaryVal)+1;
                    output += val;
                }
                System.out.println(output);
            }
        }
        
    }

    public static boolean isValid(String num){
        boolean output = true;
        for(int i = 0; i < num.length(); i++){
            char chr = num.charAt(i);
            if(chr != '1' && chr != '0'){
                output = false;
                break;
            }
        }
        return output;
    }

    public static int getBinary(String input){
        int val = Integer.parseInt(input, 2);
        return val;

    }
}

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3

Verdict: ACCEPTED

Test 6

Group: 1, 2, 3

Verdict: ACCEPTED

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

Test 8

Group: 1, 2, 3

Verdict: ACCEPTED

Test 9

Group: 1, 2, 3

Verdict: ACCEPTED

Test 10

Group: 1, 2, 3

Verdict: ACCEPTED

Test 11

Group: 1, 2, 3

Verdict: ACCEPTED

Test 12

Group: 1, 2, 3

Verdict: ACCEPTED

Test 13

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 16

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 17

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 18

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 19

Group: 2, 3

Verdict: ACCEPTED

Test 20

Group: 2, 3

Verdict: ACCEPTED

Test 21

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 22

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 23

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 24

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 25

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 26

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 27

Group: 3

Verdict: ACCEPTED

Test 28

Group: 3

Verdict: ACCEPTED