longest common prefix - Java

#1

public class testCode1 {
    public static void main(String[] args) {

        String strs[] = {"flower","flower","flower","flower"};
        String min_len = strs[0];
        int min_len_word=0;
        String prefix="";

        if(strs.length==1){
            System.out.println(strs[0]);;
        }else {

            for(int i=0;i<strs.length;i++){
                if(strs[i].length()<min_len.length()){
                    min_len=strs[i];
                }

            }

            min_len_word=min_len.length();

            boolean flag =false;
            for(int k=0;k<min_len_word;k++){
                for(int l=1;l<strs.length;l++){
                    if(strs[0].charAt(k)==strs[l].charAt(k)){
                        flag=true;
                    }else {
                        flag=false;
                        break;
                    }

                 }

                if(flag){
                    prefix=prefix+strs[0].charAt(k);
                }else{
                    break;
                }

                System.out.println(""+prefix);
            }

        }

    }

    }

#2

import java.util.Arrays;
public class longestCommonPrefix {

    //Input: strs = ["flower","flow","flight"]
    //Output: "fl"
    //Input: strs = ["dog","racecar","car"]
    //Output: ""

    public static void main(String[] args) {

        String values[] = {"abcd","abdder","abc"};
        int size = values.length;


        Arrays.sort(values);
        System.out.println(values[0]+":"+values[1]+":"+values[2]);
        int end = Math.min(values[0].length(),values[size-1].length());
        System.out.println(end);

        int i = 0;
        while (i < end && values[0].charAt(i) == values[size-1].charAt(i) )
            i++;

        System.out.println("i value"+i);
        String pre = values[0].substring(0, i);
        System.out.println(pre);

        }

    }