Merge pull request #34 from vipu18/patch-1

Add unbounded knapsack algorithm in C++

Author: admirerr

CPP/dynamic-programming/unbounded_knapsnack.cpp

@@ -0,0 +1,51 @@
+#include <iostream>
+#include <vector>
+#include <climits>
+using namespace std;
+
+// Space Optimization version (most efficient)
+class Solution
+{
+public:
+    int unboundedKnapsack(vector<int> &weight, vector<int> &value, int n, int target)
+    {
+        vector<int> prev(target + 1, 0);
+        for (int i = weight[0]; i <= target; i++)
+        {
+            prev[i] = (i / weight[0]) * value[0];
+        }
+        for (int i = 1; i < n; i++)
+        {
+            for (int tar = 0; tar <= target; tar++)
+            {
+                int nott = 0 + prev[tar];
+                int take = INT_MIN;
+                if (weight[i] <= tar)
+                    take = value[i] + prev[tar - weight[i]];
+                prev[tar] = max(nott, take);
+            }
+        }
+        return prev[target];
+    }
+};
+
+int main()
+{
+    int n, W;
+    cout << "Enter number of items: ";
+    cin >> n;
+    vector<int> wt(n), val(n);
+    cout << "Enter weights: ";
+    for (int i = 0; i < n; ++i)
+        cin >> wt[i];
+    cout << "Enter values: ";
+    for (int i = 0; i < n; ++i)
+        cin >> val[i];
+    cout << "Enter knapsack capacity: ";
+    cin >> W;
+
+    Solution sol;
+    int result = sol.unboundedKnapsack(wt, val, n, W);
+    cout << "Maximum value: " << result << endl;
+    return 0;
+}