Java/DynamicProgramming/Knapsack.java at dev · primary-code-test/Java · GitHub

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package DynamicProgramming;

/** A DynamicProgramming based solution for 0-1 Knapsack problem */

public class Knapsack {

private static int knapSack(int W, int wt[], int val[], int n) throws IllegalArgumentException {

if (wt == null || val == null) throw new IllegalArgumentException();

int i, w;

int rv[][] = new int[n + 1][W + 1]; // rv means return value

// Build table rv[][] in bottom up manner

for (i = 0; i <= n; i++) {

for (w = 0; w <= W; w++) {

if (i == 0 || w == 0) rv[i][w] = 0;

else if (wt[i - 1] <= w)

rv[i][w] = Math.max(val[i - 1] + rv[i - 1][w - wt[i - 1]], rv[i - 1][w]);

else rv[i][w] = rv[i - 1][w];

}

return rv[n][W];

}

// Driver program to test above function

public static void main(String args[]) {

int val[] = new int[] {50, 100, 130};

int wt[] = new int[] {10, 20, 40};

int W = 50;

int n = val.length;

System.out.println(knapSack(W, wt, val, n));

}