main.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"net"
	"strings"
	"time"
)

func main() {

	conn, err := net.Dial("tcp", "palindromer-bd7e0fc867d57915.elb.us-east-1.amazonaws.com:7777")
	if err != nil {
		log.Fatal("could not connect", err)
	}
	defer conn.Close()

	for {
		func() {
			t := time.Now()
			defer func() {
				log.Printf("elapsed %s\n", time.Since(t))
			}()

			reader := bufio.NewReader(conn)
			request, err := reader.ReadString('\n')
			if err != nil {
				log.Fatal("failed to read from connection", err)
			}

			if strings.HasPrefix(request, "!!!") {
				log.Fatalf("all done %q\n", request)
			}
			request = strings.TrimRight(request, "\n")
			candidates := strings.Split(request, " ")
			pals := findPalindromes(candidates)
			response := []byte(fmt.Sprintf("%s\n", strings.Join(pals, " ")))
			n, err := conn.Write(response)
			if err != nil {
				log.Fatal("write failed ", err )
			}
			if n != len(response) {
				log.Fatalf("incomplete wrote %d expectd %d", n, len(response))
			}
		}()
	}

}

func findPalindromes(words []string) []string {
	var result []string
	for _, word := range words {
		reversed := reverse(word)
		if word == reversed {
			result = append(result, reversed)
		}
	}
	return result
}

func reverse(s string) string {
	runes := []rune(s)
	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
		runes[i], runes[j] = runes[j], runes[i]
	}
	return string(runes)
}