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@ -0,0 +1,52 @@ |
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""" |
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Jeffery Russell |
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12-1-18 |
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""" |
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def knapsack(V, W, capacity): |
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""" |
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Dynamic programming implementation of the knapsack problem |
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:param V: List of the values |
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:param W: List of weights |
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:param capacity: max capacity of knapsack |
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:return: List of tuples of objects stolen in form (w, v) |
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""" |
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choices = [[[] for i in range(capacity + 1)] for j in range(len(V) + 1)] |
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cost = [[0 for i in range(capacity + 1)] for j in range(len(V) + 1)] |
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for i in range(0, len(V)): |
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for j in range(0, capacity + 1): |
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if W[i] > j: # don't include another item |
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cost[i][j] = cost[i -1][j] |
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choices[i][j] = choices[i - 1][j] |
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else: # Adding another item |
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cost[i][j] = max(cost[i-1][j], cost[i-1][j - W[i]] + V[i]) |
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if cost[i][j] != cost[i-1][j]: |
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choices[i][j] = choices[i - 1][j - W[i]] + [(W[i], V[i])] |
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else: |
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choices[i][j] = choices[i - 1][j] |
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return choices[len(V) -1][capacity] |
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def printSolution(S): |
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""" |
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Takes the output of knapsack and prints it in a |
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pretty format. |
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:param S: list of tuples representing items stolen |
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:return: None |
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""" |
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print("Thief Took:") |
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for i in S: |
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print("Weight: " + str(i[0]) + "\tValue: \t" + str(i[1])) |
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print() |
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print("Total Value Stolen: " + str(sum(int(v[0]) for v in S))) |
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print("Total Weight in knapsack: " + str(sum(int(v[1]) for v in S))) |
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values = [99,1,1,1,1, 1,1] |
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weights = [5,1,2,3,4,5,1] |
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printSolution(knapsack(values, weights, 6)) |