algoexpert.io - Knapsack_Problem

Author: Partho Biswas

README.md

@@ -143,6 +143,7 @@ A place where I upload my daily practice on Data Structure and Algorithm problem
 |45| [Max_Sum_Increasing_Subsequence](algoexpert.io/questions/Max_Sum_Increasing_Subsequence.md) | [Python](algoexpert.io/python/Max_Sum_Increasing_Subsequence.py) |
 |46| [Longest_Common_Subsequence](algoexpert.io/questions/Longest_Common_Subsequence.md) | [Python](algoexpert.io/python/Longest_Common_Subsequence.py) |
 |47| [Water_Area](algoexpert.io/questions/Water_Area.md) | [Python](algoexpert.io/python/Water_Area.py) |
+|48| [Knapsack_Problem](algoexpert.io/questions/Knapsack_Problem.md) | [Python](algoexpert.io/python/Knapsack_Problem.py) |
 
 
 

algoexpert.io/python/Knapsack_Problem.py

@@ -0,0 +1,34 @@
+
+
+# O(N*Capacity) time |  # O(N*Capacity) space
+def knapSackProblem(items, capacity):
+    knapSackValues = [[0 for x in range(0, capacity) + 1] for y in range(0, len(items) + 1)]
+    for i in range(1, len(items) + 1):
+        currentWeight = items[i - 1][1]
+        currentValue = items[i - 1][0]
+        for individualCapacity in range(0, capacity + 1):
+            if currentWeight > capacity:
+                knapSackValues[i][individualCapacity] = knapSackValues[i - 1][individualCapacity]
+            else:
+                knapSackValues[i][individualCapacity] = max(knapSackValues[i - 1][individualCapacity], knapSackValues[i - 1][individualCapacity - currentWeight] + currentValue)
+    return [knapSackValues[-1][-1], getKnapsackItems(knapSackValues, items)]
+
+
+def getKnapsackItems(knapSackValues, items):
+    sequence = []
+    i = len(knapSackValues) - 1
+    individualCapacity = len(knapSackValues[0]) - 1
+    while i > 0:
+        if knapSackValues[i][individualCapacity] == knapSackValues[i - 1][individualCapacity]:
+            i -= 1
+        else:
+            sequence.append(i - 1)
+            individualCapacity -= items[i - 1][1]
+            i -= 1
+        if individualCapacity == 0:
+            break
+    return list(reversed(sequence))
+
+
+
+