# ScalaEuler / src / com / mklinke / euler / Problem36.scala

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47``` ```/** * * * Copyright 2012 Martin Klinke, http://www.martinklinke.com. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.mklinke.euler /** * @author Martin Klinke * */ object Problem36 { def main(args: Array[String]): Unit = { val start = System.currentTimeMillis; println("Sum of decimal and binary palindromes: " + sumPalins(1, 1000000, 0)) println("Duration: " + (System.currentTimeMillis - start) + " ms"); } def sumPalins(currentN: Int, maxN: Int, currentSum: Int): Int = { if (currentN >= maxN) currentSum else sumPalins(currentN + 1, maxN, currentSum + (if (isDecimalPalindrome(currentN) && isBinaryPalindrome(currentN)) currentN else 0)) } def isDecimalPalindrome(n: Int): Boolean = { isPalindrome(n.toString.toList.map(c => c - 48)) } def isBinaryPalindrome(n: Int): Boolean = { isPalindrome(n.toBinaryString.toList.map(c => c - 48)) } def isPalindrome(n: List[Int]): Boolean = { n == n.reverse } } ```