Question

IN JAVA!!!!

Write a method that returns the longest common prefix between a phrase A and a phrase B. If the two phrases do not share a common prefix, return the empty string “no prefix”. Your method should either take two strings or two char arrays as arguments (A, B) and return a string.

Test your method in the main with these three pairings.

Example

A: snowball

B: snowcone

Return: “snow”

A: river

B: rover

Return: “r”

A: monday

B: tuesday

Return: “no prefix”

Answer 1

public class CommonPrefix {

    public static String commonPrefix(String a, String b) {
        String common = "";
        int len = Math.min(a.length(), b.length());
        for(int i = 0; i < len; ++i) {
            if(a.charAt(i) != b.charAt(i)) {
                break;
            }
            common += a.charAt(i);
        }
        if(common.isEmpty()) {
            return "no prefix";
        } else {
            return common;
        }
    }

    public static void main(String[] args) {
        System.out.println(commonPrefix("snowball", "snowcone"));
        System.out.println(commonPrefix("river", "rover"));
        System.out.println(commonPrefix("monday", "tuesday"));
    }

}

no prefix Process finished with e xit code 0