14. Longest Common Prefix | leetcode solution

 14. Longest Common Prefix

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

If there is no common prefix, return an empty string "".

 

Example 1:

Input: strs = ["flower","flow","flight"]
Output: "fl"

Example 2:

Input: strs = ["dog","racecar","car"]
Output: ""
Explanation: There is no common prefix among the input strings.

 

Constraints:

• 1 <= strs.length <= 200
• 0 <= strs[i].length <= 200
• strs[i] consists of only lowercase English letters.

solution:

class Solution {

public:

    string longestCommonPrefix(vector<string>& strs) {

        

        string res1 ="";

        int length = INT_MAX;

        for(int i = 0 ; i < strs.size() ; i++)

        {

            if(strs[i].length() < length )

                length = strs[i].length();

        }

        for(int i = 0 ; i < length ; i++)

        {

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

            {

                if(strs[j][i] != strs[j-1][i])

                    return res1;

            }

            res1 = res1 + strs[0][i];

        }

        return res1;

        

    }

};