Author: Luca Zanini

  • Largest product in a grid

    From the Project Euler Problem 11: In the 20×20 grid below, four numbers along a diagonal line have been marked in red. 08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 49 49 99 40 17 81 18 57 60 87 17 40 98…

  • Summation of primes

    From the Project Euler Problem 10: The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. checked A processor Intel® Core™ i7-2720QM CPU @ 2.20GHz × 8 takes about 6 minutes to complete this calculation.

  • Project Euler – Problem 9

    From the Project Euler Problem 9: A Pythagorean triplet is a set of three natural numbers, a b c, for which, a2 + b2 = c2 For example, 32 + 42 = 9 + 16 = 25 = 52. There exists exactly one Pythagorean triplet for which a + b + c = 1000. Find…

  • Project Euler – Problem 8

    From the Project Euler Problem 8:Find the greatest product of five consecutive digits in the 1000-digit number. 7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450 checked I wrote the digits in a file, I read the file and I set an ArrayList<Character>…

  • Unexpected value from nativeGetEnabledTags: 0

    From the release Android SDK Tools 21 a warning fills the logcat: Unexpected value from nativeGetEnabledTags: 0 I hope it will be fixed in the next release, waiting a solution I found this workaround.

  • Buttons for a view in a Custom Control

    There are standard buttons that are often added to a view that perform the basic functions (new, delete, refresh) that usually you put in a view. The code in this post is a Custom Control you can add to a XPage bound to a lotus view to insert the buttons New, Delete and Refresh. This…

  • List of the sensors in an Android device

    This is a simple app that displays all the sensors in the phone reporting the following characteristics: Name: name of the sensor Version: version of the sensor’s module Vendor: vendor of this sensor Type: type of this sensor Max Range: maximum range of the sensor Resolution: resolution of the sensor Min Delay: minimum delay allowed…

  • Project Euler – Problem 7

    From the Project Euler Problem 7:By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.What is the 10001st prime number? checked used the code for problem 3.

  • Project Euler – Problem 6

    From the Project Euler Problem 6: The sum of the squares of the first ten natural numbers is, 1^2 + 2^2 + … + 10^2 = 385 The square of the sum of the first ten natural numbers is, (1 + 2 + … + 10)^2 = 55^2 = 3025 Hence the difference between the…

  • Creating a singleton in java

    In this post I explain how to create only one object of a java class, then a single instance is available in the application. An object of this type is called singleton and a starting class can be the following: