Learn go language 0x05: the exercise code of map in go language journey

* subject ： Use mapping （map） Realization WordCount

https://tour.go-zh.org/moretypes/23
practice ： mapping
Realization WordCount. It should return a map , It contains the string s Each of them “ word ” The number of . function wc.Test A series of test cases will be executed for this function , And output success or failure .

You'll find that strings.Fields Very helpful .

* Code

package main

import (
    "golang.org/x/tour/wc"
    "strings"
)

func WordCount(s string) map[string]int {
    
    words := strings.Fields(s)
    m := make(map[string]int)
    for _, word := range words {
    
        n, ok := m[word]
        if ok == false {
    
            m[word] = 1
        } else {
    
            m[word] = n + 1
        }
    }
    return m
}

func main() {
    
    wc.Test(WordCount)
}

Running results ：

$ ./word_count.exe
PASS
 f("I am learning Go!") =
  map[string]int{
    "Go!":1, "I":1, "am":1, "learning":1}
PASS
 f("The quick brown fox jumped over the lazy dog.") =
  map[string]int{
    "The":1, "brown":1, "dog.":1, "fox":1, "jumped":1, "lazy":1, "over":1, "quick":1, "the":1}
PASS
 f("I ate a donut. Then I ate another donut.") =
  map[string]int{
    "I":2, "Then":1, "a":1, "another":1, "ate":2, "donut.":2}
PASS
 f("A man a plan a canal panama.") =
  map[string]int{
    "A":1, "a":2, "canal":1, "man":1, "panama.":1, "plan":1}

Make small changes to the code , The running result is the same as above , as follows ：

package main

import (
    "golang.org/x/tour/wc"
    "strings"
)

func WordCount(s string) map[string]int {
    
    words := strings.Fields(s)
    m := make(map[string]int)
    for _, word := range words {
    
        _, ok := m[word]  //  Changed here , No longer assigned to temporary variables 
        if ok == false {
    
            m[word] = 1
        } else {
    
            m[word]++ //  Changed here , Direct pair m[word] The value of the add 1
        }
    }
    return m
}

func main() {
    
    wc.Test(WordCount)
}