Longest public prefix of leetcode

Title Description

Write a function to find the longest common prefix in the string array .

If no common prefix exists , Returns an empty string .

Thought analysis

The longest public prefix is first public , That means everyone has , So we can get a string first , Then compare from beginning to end , That's exactly what it is ： Used to take the first one to operate , Compare the first string with the following string , Compare character by character , If you encounter different characters, it means that the same characters have disappeared , It's over , If they are the same , So the longest public is yourself .

AC Code

class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
			int num=strs.size();
			for(int i=0;strs[0][i];i++)
			{
				for(int j=1;j<num;j++)
				{
					if(strs[0][i]!=strs[j][i])
					return strs[0].substr(0,i);
				}
			}
			return strs[0];
    }
};