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Commit 0b70c8f

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Merge pull request fnplus#350 from tush38/my-new-feature2
Fractional_Knapsack_Problem.java: Implement Fractional Knapsack Probl...
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import java.util.Arrays;
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import java.util.Comparator;
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public class FractionalKnapSack
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{
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// Time complexity O(n log n)
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public static void main(String[] args)
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{
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int[] wt = {10, 40, 20, 30};
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int[] val = {60, 40, 100, 120};
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int capacity = 50;
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double maxValue = getMaxValue(wt, val, capacity);
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System.out.println("Maximum value we can obtain = " +
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maxValue);
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}
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// function to get maximum value
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private static double getMaxValue(int[] wt,
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int[] val, int capacity)
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{
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ItemValue[] iVal = new ItemValue[wt.length];
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for(int i = 0; i < wt.length; i++)
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{
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iVal[i] = new ItemValue(wt[i], val[i], i);
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}
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//sorting items by value;
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Arrays.sort(iVal, new Comparator<ItemValue>()
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{
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@Override
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public int compare(ItemValue o1, ItemValue o2)
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{
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return o2.cost.compareTo(o1.cost) ;
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}
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});
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double totalValue = 0d;
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for(ItemValue i: iVal)
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{
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int curWt = (int) i.wt;
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int curVal = (int) i.val;
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if (capacity - curWt >= 0)
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{
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// this weight can be picked while
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capacity = capacity-curWt;
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totalValue += curVal;
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}
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else
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{
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// item cant be picked whole
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double fraction = ((double)capacity/(double)curWt);
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totalValue += (curVal*fraction);
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capacity = (int)(capacity - (curWt*fraction));
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break;
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}
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}
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return totalValue;
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}
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static class ItemValue
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{
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Double cost;
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double wt, val, ind;
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public ItemValue(int wt, int val, int ind)
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{
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this.wt = wt;
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this.val = val;
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this.ind = ind;
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cost = new Double(val/wt );
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}
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}
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}

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