public String longestCommonPrefix(String[] strs) {

if(strs == null || strs.length == 0) {

return "";

}

String s = strs[0];

for(int i = 0; i < s.length(); i++) {

char current = s.charAt(i);

for(int j = 1; j < strs.length; j++) {

if(i >= strs[j].length() || strs[j].charAt(i) != current) {

return s.substring(0, i);

}

}

}

return s;

}