第15回オフラインリアルタイムどう書くの参考問題をGoで解く

問題はこちらのリンクから。
http://qiita.com/Nabetani/items/0b56395d4c9e7c64b230

Rubyで解いてみたが( http://qiita.com/nidouchi/items/3ba43c6021d1e4d54fcd )、処理時間かかりすぎなのでGoに初挑戦。結果、我慢できる時間内で処理できるようになったけれど、アルゴリズムは基本的にRuby版と変えていないので遅いのは変わらず。

package main

import "fmt"
import "strings"

func judge(chars []string) bool {
	for i := 0; i < len(chars) / 2; i++ {
		if chars[i] != chars[len(chars) - i - 1] {
			return false
		}
	}
	return true
}

func countBits(v uint) int {
	count := 0
	for i := 0; i < 32; i++ {
		if ((1<<uint(i)) & v) != 0 {
			count++
		}
	}
	return count
}

func solve(prob string) int {
	max := 0
	orgChars := strings.Split(prob,"")
	for i := 1; i < (1 << uint(len(prob))); i++ {
		cb := countBits(uint(i))
		if cb <= max {
			continue
		}
		selChars := make([]string, cb)
		k := 0
		for j := 0; j < len(prob); j++ {
			if ((1<<uint(j)) & i) != 0 {
				selChars[k] = orgChars[j]
				k++
			}
		}
		if judge(selChars) {
			max = cb
		}
	}
	return max
}

func test(prob string, ans int) {
	a := solve(prob)
	result := "NG"
	if ans == a {
		result = "OK"
	}
	fmt.Printf("%s %d %s\n", prob, a, result)
}

func main() {
/*0*/ test( "I_believe_you_can_solve",9 )    
/*1*/ test( "a",1 )    
/*2*/ test( "aa",2 )    
/*3*/ test( "aaa",3 )    
/*4*/ test( "ab",1 )    
/*5*/ test( "aabb",2 )    
/*6*/ test( "ABBA",4 )    
/*7*/ test( "Abba",2 )    
/*8*/ test( "1234567890",1 )    
/*9*/ test( "1234567890987654321",19 )    
/*10*/ test( "abcdcba",7 )    
/*11*/ test( "0a1b2c3d4c5b6a7",7 )    
/*12*/ test( "abcdcba0123210",7 )    
/*13*/ test( "abcdcba_123210",7 )    
/*14*/ test( "_bcdcba0123210",7 )    
/*15*/ test( "abcddcba0123210",8 )    
/*16*/ test( "abcdcba01233210",8 )    
/*17*/ test( "a0bc1dc2ba3210a",9 )    
/*18*/ test( "a0bc1ddc2ba3210",8 )    
/*19*/ test( "3a0bc1ddc2ba3210",10 )    
/*20*/ test( "11oooo1111o1oo1o111ooooooooooo",20 )    
/*21*/ test( "11o1111o1111oo11ooo11111ooo1oo",20 )    
/*22*/ test( "111111oo11o111ooo1o1ooo11ooo1o",21 )    
/*23*/ test( "11o1o1o11oo11o11oo111o1o1o11oo",27 )    
/*24*/ test( "oo111o1o11o1oo1ooo11o1o11o1o1o",27 )    
/*25*/ test( "1o1oo11111o1o1oo1o1o1111oo1o1o",28 )    
/*26*/ test( "QQooooQooooQQyQoyQQQyyyyQQoyoy",15 )    
/*27*/ test( "oQoooQooooQyoyQoyoyyyQQyQQQQoQ",16 )    
/*28*/ test( "yyyyyooyQyyyoyyQyyooyQoQoQQoQy",17 )    
/*29*/ test( "yyQoyQoyyQyQQoyooooyyQQyQyooQy",24 )    
/*30*/ test( "oQQooQoQyQQoyoQQoQyQyQyQoQoooo",24 )    
/*31*/ test( "oQQyQQyyQyQQoooyQQyyyQQQyyQQoy",25 )    
/*32*/ test( "WAk9iHI4jVDlStyudwTNqE138kwan2",3 )    
/*33*/ test( "c43fIu1Mlz0K9hEVOgGcUdbeB5ksa7",3 )    
/*34*/ test( "CAbYcW5VqHjzFdIkH_61PM0TsyRuie",3 )    
/*35*/ test( "jInQnUvSayrJTsQWujovbbqW0STvoj",10 )    
/*36*/ test( "iZDrvpUKgtj3FrZsZ4CLjrEgUdZzQG",11 )    
/*37*/ test( "ROgYUOu6er_DA7nB6UGquO1GUHC62R",11 )    
/*38*/ test( "Oh_be_a_fine_girl_kiss_me",9 )    
/*39*/ test( "8086_6502_6809_Z80",11 )    
/*40*/ test( "xcode_visualstudio_eclipse",11 )    
/*41*/ test( "word_excel_powerpoint_outlook",9 )    
/*42*/ test( "abcdefghijklmnopqrstuvwxyz0123",1 )
}