GV

GeezerVison

The World Wide Web, restored to 800 pixels of glory.

Home|About|Gaming cabinet|Archives|How it works|Starter sites

On this site

  • Sign in
  • ActionsCI/CD and automation
  • CodespacesCloud development environments
  • All Features
  • Documentation
  • Training
  • Certifications
  • Build with Copilot
  • Customize Copilot
  • Integrations
  • Trending repos
  • GitHub Sponsors
  • Developer articles
  • Enterprises

This view

  • Original page
  • New address

GeezerVison is showing github.com — Java/DynamicProgramming/CatalanNumber.java at master · thisxulz/Java

Expand file tree

/

CatalanNumber.java

Copy path
More file actions
More file actions

Latest commit

 

History

History
History
60 lines (48 loc) · 1.72 KB
/

CatalanNumber.java

Copy path

File metadata and controls

60 lines (48 loc) · 1.72 KB
Raw
Copy raw file
Download raw file
Open symbols panel
Edit and raw actions
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
48
49
50
51
52
53
54
55
56
57
58
59
package DynamicProgramming;
/**
* This file contains an implementation of finding the nth CATALAN NUMBER using dynamic programming
* Wikipedia: https://en.wikipedia.org/wiki/Catalan_number
*
* Time Complexity: O(n^2)
* Space Complexity: O(n)
*
* @author AMRITESH ANAND (https://github.com/amritesh19)
*/
import java.util.Scanner;
public class CatalanNumber {
/**
* This method finds the nth Catalan number
*
* @param n input n which determines the nth Catalan number
* n should be less than equal to 50 as 50th Catalan number is 6,533,841,209,031,609,592
* for n > 50, BigInteger class should be used instead long
*
* @return catalanArray[n] the nth Catalan number
*/
static long findNthCatalan(int n){
// Array to store the results of subproblems i.e Catalan numbers from [1...n-1]
long catalanArray[] = new long[n + 1];
// Initialising C₀ = 1 and C₁ = 1
catalanArray[0] = 1;
catalanArray[1] = 1;
/**
* The Catalan numbers satisfy the recurrence relation
* C₀=1 and Cn = Σ (Ci * Cn-1-i), i = 0 to n-1 , n > 0
*/
for(int i = 2; i <= n; i++){
catalanArray[i] = 0;
for(int j = 0; j < i; j++){
catalanArray[i] += catalanArray[j] * catalanArray[i - j - 1];
}
}
return catalanArray[n];
}
// Main method
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number n to find nth Catalan number (n <= 50)");
int n = sc.nextInt();
System.out.println(n + "th Catalan number is " + findNthCatalan(n));
sc.close();
}
}
You are visitor 01402520 — GeezerVison does not store the pages you look up.
Best viewed with Netscape Navigator 4.7 or Internet Explorer 6 at 800×600. No cookies required.