【Leetcode-easy】Longest Common Prefix

 1     public String longestCommonPrefix(String[] strs) {
 2         if(strs==null||strs.length==0){
 3             return "";
 4         }
 5         int count=strs[0].length();
 6         for(int i=1;i<strs.length;i++){
 7             String str1=strs[i-1];
 8             String str2=strs[i];
 9             int len=Math.min(str1.length(),str2.length());
10             if(len<count){
11                 count=len;
12             }
13             int comNum=0;
14             for(int j=0;j<count;j++){
15                 if(str1.charAt(j)==str2.charAt(j)){
16                     comNum++;
17                 }else{
18                     break;
19                 }
20             }
21             if(comNum<count){
22                 count=comNum;
23             }
24             
25         }
26         if(count==0){
27             return "";
28         }
29         return strs[0].substring(0, count);
30     }