Longest Common Prefix - Amazon Top Interview Questions

Problem Statement :

```Given a list of lowercase alphabet strings words, return the longest common prefix.

Example 1

Input
words = ["anthony", "ant", "antigravity"]

Output
"ant"

Explanation

"ant" is the longest common prefix between the three strings.```

Solution :

```                        ```Solution in C++ :

string solve(vector<string>& words) {
if (words.size() == 0) {
return "";
}

string common = "";
for (int i = 0;; i++) {
for (auto word : words) {
if (i >= word.size() || word[i] != words[0][i]) {
return common;
}
}
common += words[0][i];
}
return common;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public String solve(String[] words) {
Arrays.sort(words);
int n = words.length;
String s = words[0];
if (n == 1)
return s;
String s1 = words[n - 1];

StringBuilder res = new StringBuilder();

for (int i = 0; i < Math.min(s1.length(), s.length()); i++) {
if (s.charAt(i) == s1.charAt(i))
res.append(s.charAt(i));
else
break;
}
return res.toString();
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, words):

# O(n) to find shortest word
min_word = min(words, key=len, default="")

# O(m*n) m is number of characters in minimum word
prefix_len = 0
for idx, char in enumerate(min_word):
for word in words:
if word[idx] != char:
return min_word[:prefix_len] if prefix_len else ""

else:
continue

prefix_len += 1

return min_word[:prefix_len] if prefix_len else ""```
```

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