JavaAlgorithms/DynamicProgramming/DyanamicProgrammingKnapsack.java

package DynamicProgramming;

// A Dynamic Programming based solution
// for 0-1 Knapsack problem
public class DyanamicProgrammingKnapsack {
  static int max(int a, int b) {
    return (a > b) ? a : b;
  }

  // Returns the maximum value that can
  // be put in a knapsack of capacity W
  static int knapSack(int W, int wt[], int val[], int n) {
    int i, w;
    int K[][] = new int[n + 1][W + 1];

    // Build table K[][] in bottom up manner
    for (i = 0; i <= n; i++) {
      for (w = 0; w <= W; w++) {
        if (i == 0 || w == 0) K[i][w] = 0;
        else if (wt[i - 1] <= w) K[i][w] = max(val[i - 1] + K[i - 1][w - wt[i - 1]], K[i - 1][w]);
        else K[i][w] = K[i - 1][w];
      }
    }

    return K[n][W];
  }

  // Driver code
  public static void main(String args[]) {
    int val[] = new int[] {60, 100, 120};
    int wt[] = new int[] {10, 20, 30};
    int W = 50;
    int n = val.length;
    System.out.println(knapSack(W, wt, val, n));
  }
}