Remove Leading Zeros From String in Java

Given a string of digits, remove leading zeros from it.

Examples:

Input : 00000123569
Output : 123569

Input : 000012356090
Output : 12356090

We use StringBuffer class as Strings are immutable.

1) Count leading zeros.
2) Use StringBuffer replace function to remove characters equal to above count.

// Java program to remove leading/preceding zeros
// from a given string
import java.util.Arrays;
import java.util.List;

/* Name of the class to remove leading/preceding zeros */
class RemoveZero
{
    public static String removeZero(String str)
    {
        // Count leading zeros
        int i = 0;
        while (str.charAt(i) == '0')
            i++;

        // Convert str into StringBuffer as Strings
        // are immutable.
        StringBuffer sb = new StringBuffer(str);

        // The  StringBuffer replace function removes
        // i characters from given index (0 here)
        sb.replace(0, i, "");

        return sb.toString();  // return in String
    }

    // Driver code
    public static void main (String[] args)
    {
        String str = "00000123569";
        str = removeZero(str);
        System.out.println(str);
    }
}

Output:

123569

Remove leading Zeros From string in C++

This article is contributed by Mr. Somesh Awasthi. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.