Fractional Knapsack

alelom
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INPUTS

Values

values = "10,3,4,7" # You can change these.

Weights

weights = "2,5,1,3" # You can change these.

Knapsack total capacity

capacity = 10

ALGORITHM

def fractional_knapsack(values, weights, capacity): # index = [0, 1, 2, ..., n - 1] for n items index = list(range(len(values)))

# value/weight ratio
ratio = [v / w for v, w in zip(values, weights)]

# index sorted by descending value/weight ratio
index.sort(key=lambda i: ratio[i], reverse=True)
print(index)

max_value = 0

fractions = [0] * len(values)

for i in index:
    if weights[i] <= capacity:
        fractions[i] = 1
        max_value += values[i]
        capacity -= weights[i]

    else:
        
        fractions[i] = capacity / weights[i]
        max_value += values[i] * capacity / weights[i]
        break

return max_value, fractions

Process inputs

values = [int(v) for v in values.split(',')] weights = [int(w) for w in weights.split(',')]

FUNCTION CALL

max_value, fractions = fractional_knapsack(values, weights, capacity)

Output

print('Total value that can be carried:', max_value) print('Fractions by which to multiply the items:', fractions)

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