leetcode第14题最长公共前缀

需要注意strs为空的情况

class Solution {
    private int getSumString(String a,String b){
        int i=0;
        while(i<a.length()&&i<b.length()){
            if(a.charAt(i)!=b.charAt(i))break;
            i++;
        }
        return i;
    }
    
    public String longestCommonPrefix(String[] strs) {
        if(strs.length==0)return "";
        int publicLength = strs[0].length();
        for(int i=0;i<strs.length;i++){
            int sumStr = getSumString(strs[0],strs[i]);
            if(sumStr<publicLength)publicLength=sumStr;
        }
        if(publicLength<=0)return "";
        else return strs[0].substring(0,publicLength);
    }
}