Subsetsum

dynamic_programming/subsetsum.cpp

@@ -0,0 +1,36 @@
+
+// A recursive solution for subset sum problem 
+#include <stdio.h> 
+
+// Returns true if there is a subset of set[] with sun equal to given sum 
+bool isSubsetSum(int set[], int n, int sum) 
+{ 
+   // Base Cases 
+   if (sum == 0) 
+     return true; 
+   if (n == 0 && sum != 0) 
+     return false; 
+
+   // If last element is greater than sum, then ignore it 
+   if (set[n-1] > sum) 
+     return isSubsetSum(set, n-1, sum); 
+
+   /* else, check if sum can be obtained by any of the following 
+      (a) including the last element 
+      (b) excluding the last element   */
+   return isSubsetSum(set, n-1, sum) ||  
+                        isSubsetSum(set, n-1, sum-set[n-1]); 
+} 
+
+// Driver program to test above function 
+int main() 
+{ 
+  int set[] = {3, 34, 4, 12, 5, 2}; 
+  int sum = 9; 
+  int n = sizeof(set)/sizeof(set[0]); 
+  if (isSubsetSum(set, n, sum) == true) 
+     printf("Found a subset with given sum"); 
+  else
+     printf("No subset with given sum"); 
+  return 0; 
+}