Skip to main content

Count Divisors : Compute number of integers divisible by k in range [a..b].

Task description
Write a function:
class Solution { public int solution(int A, int B, int K); }
that, given three integers A, B and K, returns the number of integers within the range [A..B] that are divisible by K, i.e.:
{ i : A ≤ i ≤ B, i mod K = 0 }
For example, for A = 6, B = 11 and K = 2, your function should return 3, because there are three numbers divisible by 2 within the range [6..11], namely 6, 8 and 10.
Assume that:
  • A and B are integers within the range [0..2,000,000,000];
  • K is an integer within the range [1..2,000,000,000];
  • A ≤ B.
Complexity:
  • expected worst-case time complexity is O(1);
  • expected worst-case space complexity is O(1).


class Solution { public int solution(int A, int B, int K) { // write your code in Java SE 8 long a=A; long b=B; long k=K; long count=0; long i=a%k; //System.out.println(a+" "+b+" "+k); if(i!=0){ a=a+Math.abs(i-k); } long j=b%k; if(j!=0){ b=b-(Math.abs(j)); } if(a!=b){ if(a%k==0) count=1; count=count+(b-a)/k; }else{ if(a==0 && b==0){ count=1; }else if(a%k==0){ count=(b/a); }else{ count=0; } } return (int)count; } }


100%                               100 out of 100 points


Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(1)
expand allExample tests
▶
example 
A = 6, B = 11, K = 2
✔
OK
expand allCorrectness tests
▶
simple 
A = 11, B = 345, K = 17
✔
OK
▶
minimal 
A = B in {0,1}, K = 11
✔
OK
▶
extreme_ifempty 
A = 10, B = 10, K in {5,7,20}
✔
OK
▶
extreme_endpoints 
verify handling of range endpoints, multiple runs
✔
OK
expand allPerformance tests
▶
big_values 
A = 100, B=123M+, K=2
✔
OK
▶
big_values2 
A = 101, B = 123M+, K = 10K
✔
OK
▶
big_values3 
A = 0, B = MAXINT, K in {1,MAXINT}
✔
OK
▶
big_values4 
A, B, K in {1,MAXINT}
✔

Comments

Post a Comment

Popular posts from this blog

Java Interface

Problem Statement A Java interface can only contain method signatures and fields. Interface can be used to achieve polymorphism. In this problem you will practice your knowledge on interfaces. You are given an interface   AdvancedArithmetic   which contains a method signature   public abstract int divisorSum(int n) . You need to write a class called MyCalculator which implements the interface. divisorSum   function just takes an integer as input and return the sum of all its divisors. For example divisors of 6 are 1,2,3 and 6, so   divisorSum   should return 12. Value of n will be at most 1000. Read the partially completed code in the editor and complete it. You just need to write the MyCalculator class only.   Your class shouldn't be public. Sample Input 6 Sample Output I implemented: AdvancedArithmetic 12 Explanation Divisors of 6 are 1,2,3 and 6. 1+2+3+6=12. import java.util.*; interface AdvancedArithmetic{   p...
Post a Comment
Read more

change directory (cd) function for an abstract file system ( Java Implementation )

Write a function that provides change directory (cd) function for an abstract file system. Notes: Root path is '/'. Path separator is '/'. Parent directory is addressable as "..". Directory names consist only of English alphabet letters (A-Z and a-z). For example, new Path("/a/b/c/d").cd("../x").getPath() should return "/a/b/c/x". Note: The evaluation environment uses '\' as the path separator. public class Path {     private String path;     public Path(String path) {         this.path = path;     }     public String getPath() {         return path;     }     public Path cd(String newPath) {         //throw new UnsupportedOperationException("Waiting to be implemented."); String[] newP=newPath.split("/");     String[] oldP=path.split("/");     int lnCount=0;     for(String str:newP){     if(st...
6 comments
Read more

Java Abstract Class

Problem Statement A Java abstract class is a class that can't be instantiated, that means you cannot create new instances of an abstract class. It works as a base for subclasses. You should learn about Java Inheritence before attempting this challenge. Following is an example of abstact class: abstract class Book {     String title;     abstract void setTitle(String s);     String getTitle()     {         return title;     } } If you try to create an instance of this class like the following line you will get an error: Book new_novel=new Book(); You have to create another class that extends the abstract class. Then you can create instance of the new class. Notice that   setTitle   method is abstract too and has no body. That means you must implement the body of the that method in the child class. In the editor we have provided ...
Post a Comment
Read more