@H_403_0@package main
import (
"bufio"
"fmt"
"os"
)
func main() {
counts := make(map[string]int)
files := os.Args[1:]
if len(files) == 0 {
countLines(os.Stdin,counts)
} else {
for _,arg := range files {
f,err := os.Open(arg)
if err != nil {
fmt.Fprintf(os.Stderr,"dup2: %v\n",err)
continue
}
countLines(f,counts)
f.Close()
}
}
for line,n := range counts {
fmt.Printf("%d\t%s\n",n,line)
}
}
func countLines(f *os.File,counts map[string]int) {
input := bufio.NewScanner(f)
for input.Scan() {
counts[input.Text()]++
}
// NOTE: ignoring potential errors from input.Err()
}
go run main.go a.txt
另一种方法：
package main
import (
"fmt"
"io/IoUtil"
"os"
"strings"
)
func main() {
counts := make(map[string]int)
for _,filename := range os.Args[1:] {
data,err := IoUtil.ReadFile(filename)
if err != nil {
fmt.Fprintf(os.Stderr,"dup3: %v\n",err)
continue
}
for _,line := range strings.Split(string(data),"\n") {
counts[line]++
}
}
for line,n := range counts {
if n > 1 {
fmt.Printf("%d\t%s\n",line)
}
}
}
