ch3/ch3-05

[giscus[bot]]

ch3/ch3-05

中文版

https://gopl-zh.github.io/ch3/ch3-05.html

[zb81]

3.10

func comma(s string) string {
	var buf bytes.Buffer
	for i := 0; i < len(s); i++ {
		if i > 0 && (len(s)-i)%3 == 0 {
			buf.WriteByte(',')
		}
		buf.WriteByte(s[i])
	}
	return buf.String()
}

[zb81]

3.11
刚入门，水平有限，欢迎交流

func comma(s string) string {
	var buf bytes.Buffer

	// 如果以 +/- 号开头，设置 start 为 1，将 +/- 号写入 buf
	var start int
	if s[0] == '+' || s[0] == '-' {
		start = 1
		buf.WriteByte(s[0])
	} else {
		start = 0
	}

	// 获取小数点的索引，根据 start 和 end 获取整数部分
	end := strings.Index(s, ".")
	ints := s[start:end]

	// 对整数部分进行 comma 操作
	for i := 0; i < len(ints); i++ {
		if i > 0 && (len(ints)-i)%3 == 0 {
			buf.WriteByte(',')
		}
		buf.WriteByte(ints[i])
	}

	// 拼接小数点及之后的部分
	rest := s[end:]
	for i := 0; i < len(rest); i++ {
		buf.WriteByte(rest[i])
	}

	return buf.String()
}

[Yangfsssss]

3.12
刚入门，水平有限，欢迎交流

func isMixedTwoStrings(s1, s2 string) bool {
	l1, l2 := len(s1), len(s2)
	if l1 != l2 {
		return false
	}

	m1 := make(map[rune]int)
	m2 := make(map[rune]int)

	for _, v := range s1 {
		m1[v]++
	}
	for _, v := range s2 {
		m2[v]++
	}

	result := true
	for k := range m1 {
		if m1[k] != m2[k] {
			result = false
		}
	}

	return result
}

[yinxlLearning]

大体上应该是对的

// 3.12
func isEqualOutOfOrder(s1 string, s2 string) bool {
	var mp = make(map[rune]int)

	for _, c := range s1 {
		mp[c]++
	}

	for _, c := range s2 {
		mp[c]--
	}

	for _, v := range mp {
		if v != 0 {
			return false
		}
	}

	return true
}
// 3.10
func comma(s string) string {
	split := strings.Split(s, ".")
	var sz = split[0]
	var sf = split[1]

	var sNew = bytes.Buffer{}
	for i := 0; i < len(sz); i++ {
		sNew.WriteByte(sz[i])
		if i%3 == 0 {
			sNew.WriteByte(',')
		}
	}
	bz := getSZ(sz)
	bf := getSF(sf)
	return fmt.Sprintf("%s.%s\n", bz.Bytes(), bf.Bytes())
}

func getSF(sf string) bytes.Buffer {
	buffer := bytes.Buffer{}
	for i := 0; i < len(sf); i++ {
		if i%3 == 0 && i != 0 {
			buffer.WriteByte(',')
		}
		buffer.WriteByte(sf[i])
	}
	return buffer
}

func getSZ(sz string) bytes.Buffer {
	nz := len(sz)
	buffer := bytes.Buffer{}
	var i int = 0
	for i = 0; i < nz%3; i++ {
		buffer.WriteByte(sz[i])
	}
	for ; i < nz; i++ {
		if (i-nz%3)%3 == 0 {
			buffer.WriteByte(',')
		}
		buffer.WriteByte(sz[i])
	}
	return buffer
}

[SuperZ3]

没有什么是循环解决不了的

package main

import (
	"fmt"
	"bytes"
	"strings"
)

func main() {
	fmt.Println(comma("+9909999.999"))
	fmt.Println(commaBuf("9999999"))
}

func comma(s string) string {
    n := len(s)
    if n <= 3 {
        return s
    }
	add := strings.LastIndex(s, "+")
	min := strings.LastIndex(s, "-")

	if add == 0 {
		return "+" + comma(s[add+1:])
	}

	if min == 0 {
		return "-" + comma(s[add+1:])
	}

	if dot := strings.LastIndex(s, "."); dot >= 0 {
		return comma(s[:dot]) + "." + comma(s[dot+1:])
	}
    return comma(s[:n-3]) + "," + s[n-3:]
}

func commaBuf(s string) string {
	n := len(s)
    if n <= 3 {
        return s
    }

	var buf bytes.Buffer
	for i := n - 1;i >= 0;i-- {
		if i > 0 && i % 3 == 0 {
			buf.WriteByte(s[i])
			buf.WriteString(",")
		} else {
			buf.WriteByte(s[i])
		}
	}
	return buf.String()
}

[GSteve-Paul]

//3.10 + 3.11
func comma(s string) string {
	var buf bytes.Buffer
	var s1, s2 string

	var dotIdx int = strings.Index(s, ".")
	if dotIdx == -1 {
		var sgn, _ = utf8.DecodeRuneInString(s)
		if sgn == '+' || sgn == '-' {
			s = s[1:]
			buf.WriteRune(sgn)
		}
		for i, ch := range s {
			buf.WriteRune(ch)
			if (len(s)-1-i)%3 == 0 && i != len(s)-1 {
				buf.WriteRune(',')
			}
		}
		return buf.String()
	}

	var sgn, _ = utf8.DecodeRuneInString(s)
	if sgn == '+' || sgn == '-' {
		s1 = s[1:dotIdx]
		buf.WriteRune(sgn)
	} else {
		s1 = s[:dotIdx]
	}
	s2 = s[dotIdx+1:]

	for i, ch := range s1 {
		buf.WriteRune(ch)
		if (len(s1)-1-i)%3 == 0 && i != len(s1)-1 {
			buf.WriteRune(',')
		}
	}
	buf.WriteRune('.')
	for i, ch := range s2 {
		if i%3 == 0 && i != 0 {
			buf.WriteRune(',')
		}
		buf.WriteRune(ch)
	}
	return buf.String()
}

//3.12
func strMixed(s1, s2 string) bool {
	var mp map[rune]int = make(map[rune]int)
	for _, ch := range s1 {
		mp[ch]++
	}
	for _, ch := range s2 {
		mp[ch]--
	}
	for _, cnt := range mp {
		if cnt != 0 {
			return false
		}
	}
	return true
}

[newarabbit]

3.10

func comma(s string) string {
	values := []byte(s)
	var buf bytes.Buffer
	for i, _ := range values {
		if i%3 == 0 && i != 0 {
			buf.WriteByte(',')
		}
		buf.WriteByte(values[i])
	}
	return buf.String()
}

[lwc18]

package comma

// comma inserts commas in a non-negative decimal integer string.
func Comma(s string) string {
var res string
n := len(s)
j := 0
for i := 0; i < n; i++ {
if s[i] == '+' || s[i] == '-' {
res += s[i : i+1]
continue
}
if s[i] == '.' {
res += s[i : i+1]
j = 0
continue
}
if j == 3 {
res += ","
j = 0
}
res += s[i : i+1]
j++
}
return res
}
func IsSameStr(s1 string, s2 string) bool {
var list1 [256]int
var list2 [256]int
if len(s1) != len(s2) {
return false
}
for i := 0; i < len(s1); i++ {
list1[s1[i]]++
list2[s2[i]]++
}
for i := 0; i < len(list1); i++ {
if list1[i] != list2[i] {
return false
}
}
return true
}

[yu520]

func Comma1(s string) string {
var buf bytes.Buffer
count := len(s)
for i, v := range s {
if i > 0 && (count-i)%3 == 0 {
buf.WriteString(",")
}
fmt.Fprintf(&buf, "%c", v)
}
return buf.String()
}