Longest Common Prefix in a set of strings

Overview

An array of strings is given. The objective is to find the longest common prefix from that array of strings.  It should output an empty string if there is no common prefix.

Example 1

Input: ["fan", "fat", "fame"]
Output: "fa"

Example 2

Input: ["bat", "van", "cat"]
Output: ""

Program

Below is the program for the same

package main

import "fmt"

func longestCommonPrefix(strs []string) string {
	lenStrs := len(strs)

	if lenStrs == 0 {
		return ""
	}

	firstString := strs[0]

	lenFirstString := len(firstString)

	commonPrefix := ""
	for i := 0; i < lenFirstString; i++ {
		firstStringChar := string(firstString[i])
		match := true
		for j := 1; j < lenStrs; j++ {
			if (len(strs[j]) - 1) < i {
				match = false
				break
			}

			if string(strs[j][i]) != firstStringChar {
				match = false
				break
			}

		}

		if match {
			commonPrefix += firstStringChar
		} else {
			break
		}
	}

	return commonPrefix
}

func main() {
	output := longestCommonPrefix([]string{"fan", "fat", "fame"})
	fmt.Println(output)

	output = longestCommonPrefix([]string{"bat", "van", "cat"})
	fmt.Println(output)
}

Output:

"fa"
""

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