View difference between Paste ID: XFgrFMUZ and A83KzbS3

 import java.io.FileNotFoundException;
 import java.io.FileReader;
 import java.util.Arrays;
 import java.util.Scanner;
 
 class Problem implements Comparable<Problem>{
     int p, d, t;
     public Problem(int p, int d, int t) {
         this.p = p;
         this.d = d;
         this.t = t;
     }
 
     int pointsLeft(int t1) {
         return p - d*(t+t1);
     }
 
     double ratio() {
         return ((double)t)/((double)d);
     }
 
     public String toString() {
         return ""+p+' '+d+' '+t;
     }
 
     @Override
     public int compareTo(Problem o) {
         return new Integer(t*o.d).compareTo(o.t*d);
     }
 }
 
 public class Kelvin {
 
     // N is total number of problems
     // T is bigger than the maximum time any problem can last
     static int N, T = 40000;
 
     static Problem[] a;
 
     // arrays to store values for dynamic programming
     static int[] dp = new int[T];
     static int[] dp2 = new int[T];
 
     @SuppressWarnings("resource")
     public static void main(String[] args) throws FileNotFoundException {
         Scanner s = new Scanner(new FileReader("kelvin.txt"));
         N = s.nextInt();
         a = new Problem[N+1];
         for(int i = 1; i <= N; i++)
             a[i] = new Problem(s.nextInt(),s.nextInt(),s.nextInt());
 
         // add a place holder for problem at position 0
         a[0] = new Problem(0, 1, 0);
 
         // sorted based on t/d
         Arrays.sort(a);
 
         for(int t = 0; t < T; t++) {
                 dp[t] = 0;
                 dp2[t] = 0;
         }
         for(int i = a.length-1; i >= 1; i--) {
 
             // update dp values
             for(int t = T-1; t >= 0; t--)
                 if(a[i].pointsLeft(t) > 0)
                     dp2[t] = Math.max(dp[t], dp[t+a[i].t]+a[i].pointsLeft(t));
 
             // shift new dp values back to first array
             for(int t = 0; t < T; t++)
                 dp[t] = dp2[t];
         }
         System.out.println(dp[0]);
     }
 }