JavaEasyNumbers10 min

Reverse the digits of an integer

Return the reversed integer, preserving its sign and discarding leading zeros. Follow the stated ordering and edge-case conventions exactly. Interviewers use this task to probe algorithm selection, invariants, and boundary handling.

Input

One signed integer n.

Output

Return the reversed integer, preserving its sign and discarding leading zeros.

Constraints

-2147483648 <= n <= 2147483647.

Example

Input

Output

Example 2 input

1000000000

Output

This example exercises trailing zero removal.

Public test cases (2)

Input
```
120
```
Expected output
```
21
```
Input
```
-450
```
Expected output
```
-54
```

Hints (2)

Identify the state needed to avoid recomputing work for each element.
Accumulate the final digit into a long and remove it from the input.

Target complexity: time O(d) · space O(1)

Your solution

import java.util.*;
import java.math.BigInteger;

public class Main {
    
    static String reverse_number(Scanner s) {
        while (s.hasNextLine()) s.nextLine();
        // your code
        return "";
    }
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        System.out.println(reverse_number(s));
    }
}

Standard input

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Reference solution

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All Java programs

Reverse the digits of an integer

Input

Output

Constraints

Example

Public test cases (2)

Your solution

Reference solution

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