Maps exercise solution http://tour.golang.org/#43

output

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

Program exited.

solution.go

package main

import (
    "strings"
    "code.google.com/p/go-tour/wc"
)

func WordCount(s string) map[string]int {
    var x = make(map[string]int)
    for _,v := range strings.Fields(s) {
    	x[v]++
    }
    return x
}

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