[LeetCode]Longest Common Prefix

Write a function to find the longest common prefix string amongst an array of strings.

思考：依次比较字符串的第i个字符，不同退出循环。

class Solution {
public:
    string longestCommonPrefix(vector<string> &strs) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
        string res="";
		if(strs.size()==0) return res;
		if(strs.size()==1) return strs[0];
		int i,j;
		for(i=0;i<strs[0].size();i++)
		{
		    char temp=strs[0][i];
		    for(j=1;j<strs.size();j++)
		    {
		        if(strs[j].size()==i) return res;
		        if(strs[j][i]!=temp) return res;
		    }
		    res+=temp;
		}
		return res;
    }
};