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

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 lower-case English letters.

Solution:

def longestCommonPrefix(self, strs):
    prefix=""
    if len(strs)==0: return prefix
    
    for i in xrange(len(min(strs))):
        c=strs[0][i]
        if all(a[i]==c for a in strs):
            prefix+=c
        else:
            break
    return prefix

Solution 1:

def longestCommonPrefix(self, strs):
        """
        :type strs: List[str]
        :rtype: str
        """
        prefix=[]
        num = len(strs)
        for x in zip(*strs):
            if len(set(x)) == 1:
                prefix.append(x[0])
            else:
                break
        return "".join(prefix) ```

Solution 2:

class Solution:
    def longestCommonPrefix(self, strs):
        """
        :type strs: List[str]
        :rtype: str
        """
        if not strs: return ""
        if len(strs) == 1: return strs[0]
        
        strs.sort()
        p = ""
        for x, y in zip(strs[0], strs[-1]):
            if x == y: p+=x
            else: break
        return r