LeetCode-14. Longest Common Prefix

[ninehills]

问题

https://leetcode.com/problems/longest-common-prefix/#/description

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

思路

两两对比找出最长的prefix字符串，然后顺序对比下去

解答

package main

import "fmt"

// ----------------------
func longestCommonPrefix(strs []string) string {
	common_prefix := ""
	for index, str := range strs {
		if index == 0 {
			common_prefix = str
			continue
		}
		common_prefix = getCommonPrefix(common_prefix, str)
	}
	return common_prefix
}

func getCommonPrefix(a string, b string) string {
	//fmt.Println(a, b)
	b_length := len(b)
	for index, char := range a {
		if index < b_length {
			//fmt.Println(index, byte(char), b[index])
			if byte(char) == b[index] {
				continue
			} else {
				return a[:index]
			}
		} else {
			return b
		}
	}
	return a
}

// ----------------------

func main() {
	var strs = []string{"MMMCMLXXXIX", "MMMCsd", "MMIDFSDF"}
	fmt.Println(longestCommonPrefix(strs))
	strs = []string{"", "b"}
	fmt.Println(longestCommonPrefix(strs))
	strs = []string{"b", "b"}
	fmt.Println(longestCommonPrefix(strs))
}