(UVA) Subsequence - Solution

Link to the problem: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=3562

The solution below used a technique called Sliding Window to solve this problem.


import java.io.*;
import java.util.*;

class Main {
    public void process() throws NumberFormatException, IOException {
        Scanner sc = new Scanner(System.in);
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        while (sc.hasNext()) {
            int numNumbers = sc.nextInt();
            int desiredMinSum = sc.nextInt();
           
            int sum = 0;
            int pointerLeft = 0;
            int minElements = Integer.MAX_VALUE;
            int[] numbers = new int[numNumbers];
            for (int pointerRight = 0; pointerRight < numNumbers; pointerRight++) {
                numbers[pointerRight] = sc.nextInt();
                sum += numbers[pointerRight];
                while (sum >= desiredMinSum) {
                    minElements = Math.min(minElements, pointerRight-pointerLeft+1);
                    sum -= numbers[pointerLeft++];            
                }
            }
           
            minElements = (minElements == Integer.MAX_VALUE) ? 0 : minElements;
            bw.write(minElements+"\n");
        }          
                                              
        bw.flush();
        bw.close();
       
        return;
    }
   
    public static void main(String[] args) throws NumberFormatException, IOException {
        Main m = new Main();
        m.process();
       
        System.exit(0);
    }
}