class Solution {
    public String longestCommonPrefix(String[] strs) {
        String s=strs[0];
        int l=s.length(), count=0;
        while(l>0){
            count=0;
            for(String str:strs){
                if(str.startsWith(s.substring(0, l))) count++;
            }
            if(count==strs.length) return s.substring(0, l);
            l--;
        }
        return "";
    }
}