Java: Find the number of combinations
Java Basic: Exercise-241 with Solution
Write a Java program to find the number of combinations that satisfy p + q + r + s = n where n is a given number <= 4000 and p, q, r, s range from 0 to 1000.
Sample Solution:
Java Code:
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Input a positive integer:");
int[] temp = new int[2001];
int[] ans = new int[4001];
for(int i=0;i<=1000;i++){
for(int j=0;j<=1000;j++){
temp[i+j]++;
}
}
for(int i=0;i<=2000;i++){
for(int j=0;j<=2000;j++){
ans[i+j]+=temp[i]*temp[j];
}
}
int n = sc.nextInt();
System.out.println("Number of combinations of a,b,c,d:");
System.out.println(ans[n]);
}
}
Sample Output:
Input a positive integer: 252 Number of combinations of a,b,c,d: 2731135
Flowchart:

Java Code Editor:
Contribute your code and comments through Disqus.
Previous: Write a Java program that compute the maximum value of the sum of the passing integers.
Next: Write a Java program to which adds up columns and rows of given table as shown in the specified figure.
What is the difficulty level of this exercise?
Test your Programming skills with w3resource's quiz.
- Weekly Trends
- Python Interview Questions and Answers: Comprehensive Guide
- Scala Exercises, Practice, Solution
- Kotlin Exercises practice with solution
- MongoDB Exercises, Practice, Solution
- SQL Exercises, Practice, Solution - JOINS
- Java Basic Programming Exercises
- SQL Subqueries
- Adventureworks Database Exercises
- C# Sharp Basic Exercises
- SQL COUNT() with distinct
- JavaScript String Exercises
- JavaScript HTML Form Validation
- Java Collection Exercises
- SQL COUNT() function
- SQL Inner Join