Go: find the longest common prefix in a set of strings

Finding the longest common prefix in a series of strings is a common problem in programming. This can be useful in many situations, such as in data management or input validation. In this article, we will explore how to solve this problem using the Go programming language.

The first step to solving this problem is to create a function that takes a series of input strings and returns the longest common prefix. Here's how you can do it in Go:

package main

import (
     "strings"
)

func findCommonPrefix(strings []string) string {
     // Handle the case where the slice is empty
     if len(strings) == 0 {
         return ""
     }

     // Initialize the common prefix with the first string
     prefix := strings[0]

     // Compare the prefix with the other strings
     for _, str := range strings {
         for !strings.HasPrefix(str, prefix) {
             // Progressively reduce the prefix until it matches
             prefix = prefix[:len(prefix)-1]
         }
     }

     return prefix
}

In this function, we start with the first element of the string slice as the initial common prefix. Then, we compare this prefix to every other string in the slice using strings.HasPrefix to check if it starts with the current prefix. If the prefix doesn't match, we progressively reduce it until it matches all strings or becomes empty.

Here is an example of how you can test the function:

package main

import (
     "fmt"
)

func main() {
     strings := []string{"house", "waterfall", "barracks", "castle"}
     prefix := findCommonPrefix(strings)
     fmt.Println("The common prefix is:", prefix)
}

In the example above, we have a slice of strings starting with "cas", so the common prefix should be "cas".

Conclusions

Finding the longest common prefix in a set of strings is a useful and common problem in programming. With Go, you can solve this problem efficiently by using the strings.HasPrefix function. Simply create a function that compares the prefix to each string in the series and progressively reduces the prefix until it matches all strings or becomes empty. Once the feature has been implemented and tested, it can be used to easily find the common prefix in a variety of situations.