Knapsack with Python3

class ItemValue:

    def __init__(self, wt, val, ind):

        self.wt = wt

        self.val = val

        self.ind = ind

        self.cost = val // wt

  

    def __lt__(self, other):

        return self.cost < other.cost

  

# Greedy Approach

class FractionalKnapSack:

    def getMaxValue(wt, val, capacity):




        iVal = []

        for i in range(len(wt)):

            iVal.append(ItemValue(wt[i], val[i], i))

  

        iVal.sort(reverse = True)

  

        totalValue = 0

        for i in iVal:

            curWt = int(i.wt)

            curVal = int(i.val)

            if capacity - curWt >= 0:

                capacity -= curWt

                totalValue += curVal

            else:

                fraction = capacity / curWt

                totalValue += curVal * fraction

                capacity = int(capacity - (curWt * fraction))

                break

        return totalValue

  

# Driver Code

if __name__ == "__main__":

    wt = [15, 20, 25]

    val = [10, 15, 18]

    capacity = 20

  

    maxValue = FractionalKnapSack.getMaxValue(wt, val, capacity)

    print("Maximum value in Knapsack = ", maxValue)