Valid Number go语言实现

Valid Number

题目描述

Given two binary strings, return their sum (also a binary string).
For example,
a ="11"
b ="1"
Return"100"

思路：

• 字串先对齐，再相加，再进。

细节：

• 用字节数组处理字串。

解：

package main

import "fmt"

func addBinary(a string, b string) string {
    var maxLen int
    switch len(a) > len(b) {
    case true:
        maxLen = len(a)
    case false:
        maxLen = len(b)
    }

    aByte := make([]byte,maxLen+1)
    for idx,_ := range aByte {
        aByte[idx] = 48
    }
    bByte := make([]byte,maxLen+1)
    for idx,_ := range bByte{
        bByte[idx] = 48
    }
    for i := 0; i < len(a); i++ {
        aByte[i+maxLen-len(a)+1] = a[i]
    }
    for i := 0; i < len(b); i++ {
        bByte[i+maxLen-len(b)+1] = b[i]
    }
    preString := make([]byte,maxLen+1)
    for i := 0; i < maxLen+1; i++ {
        preString[i] = aByte[i]+bByte[i]- 48
    }
    for i := maxLen; i > 0; i-- {
        if preString[i] == 50 {
            preString[i] = 48
            preString[i-1] = preString[i-1]+1

        }else if preString[i] == 51 {
            preString[i] = 49
            preString[i-1] = preString[i-1]+1
        }
    }
    if preString[0] == 49 {
        return string(preString)
    }
    return string(preString[1:])
}


func main()  {
    a := "11"
    b := "1"
    fmt.Print(addBinary(a,b))
}