Create subset_sum.py

subset_sum.py

@@ -0,0 +1,32 @@
+# Python implementation for subset sum
+# problem using recursion
+def isSubsetSumRec(arr, n, sum):
+
+    # Base Cases
+    if sum == 0:
+        return True 
+    if n == 0:
+        return False
+
+    # If the last element is greater
+    # than the sum, ignore it
+    if arr[n - 1] > sum:
+        return isSubsetSumRec(arr, n - 1, sum)
+
+    # Check if sum can be obtained by including
+    # or excluding the last element
+    return (isSubsetSumRec(arr, n - 1, sum) or 
+            isSubsetSumRec(arr, n - 1, sum - arr[n - 1]))
+
+def isSubsetSum(arr, sum):
+    return isSubsetSumRec(arr, len(arr), sum)
+
+if __name__ == "__main__":
+
+    arr = [3, 34, 4, 12, 5, 2]
+    sum = 9
+
+    if isSubsetSum(arr, sum):
+        print("True")
+    else:
+        print("False")