doukaku E17

hidoi.go

package main

import (
	"fmt"
	"strings"
	"strconv"
	"math"
)

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)
}

func list_with_empty(min int, max int, b int) []string {
	tmp := []string{""}
	for i := min; i < max; i++ {
		s := strconv.FormatInt(int64(i), b)
		tmp = append(tmp, s)
	}
	return tmp
}

func solve_(min int64, max int64, b int) int {
	x := int(math.Sqrt(float64(max)))
	result := 0

	for _, s := range list_with_empty(1, x, b) {
		rev_s := Reverse(s)
		for _, c := range list_with_empty(0, b, b) {
			t := fmt.Sprintf("%s%s%s", s, c, rev_s)
			n, _ := strconv.ParseInt(t, b, 64)
			if min <= n && n < max {
				result++
			}
		}
	}

	return result
}

func solve(input string) string {
	var inputs []int64
	for _, v := range strings.Split(input, ",") {
		n, _ := strconv.ParseInt(v, 10, 64)
		inputs = append(inputs, n)
	}

	min := inputs[0]
	max := inputs[1]
	b := inputs[2]
	count := solve_(min, max, int(b))

	return fmt.Sprint(count)
}

func test(input string, expected string) {
	actual := solve(input)
	if actual == expected {
		fmt.Println("ok")
	} else {
		fmt.Printf("!!!! %s : %s : %s\n", input, expected, actual)
	}
}

func tests() {
	test("12,34,5", "5")
	test("10,11,10", "0")
	test("1,100,3", "18")
	test("11,12,10", "1")
	test("12,13,10", "0")
	test("123,456,7", "33")
	test("38,274,14", "17")
	test("98,76543,2", "535")
	test("987,6543,2", "103")
	test("5057,5202,3", "2")
	test("98,76543,21", "589")
	test("987,6543,21", "264")
	test("1097,2889,11", "35")
	test("2764,6482,17", "132")
	test("16333,24085,8", "121")
	test("21759,67173,20", "114")
	test("32026,57805,22", "53")
	test("188318,407853,6", "523")
	test("51669,116065,30", "72")
	test("294104,515248,32", "216")
	test("444257,740280,15", "1316")
	test("645098,2741620,9", "2876")
	test("12345,987654321,2", "62684")
	test("2467130,8433468,2", "2902")
	test("323901,4712975,10", "4389")
	test("12345,987654321,36", "67446")
	test("3969344,4086910,24", "205")
	test("19743263,83912295,5", "11553")
	test("6349529,39870823,10", "6637")
	test("66160071,153732445,5", "5605")
	test("18799557,189007582,14", "33741")
	test("78547566,225312226,20", "18346")
	test("143084571,506549072,18", "62323")
	test("2099642384,2789567569,6", "14787")
}

func main() {
	tests()
}

hidoi.hs

import Data.List.Split (splitOn)
import Control.Lens ((^.), (^?!), re)
import Numeric.Lens (base)

solve = show . gen . map read . splitOn ","
gen [mn,mx,b] = length [n | n <- rs, mn <= n && n < mx]
  where
    rs = map (toN b) $ tail $ concatMap gen' $ "" : map (toS b) [1..(floor$sqrt$toEnum mx)]
    gen' s = [s ++ c ++ reverse s | c <- "" : map (toS b) [0..b-1]]
toN b s = s ^?! base b
toS b n = n ^. re (base b)