count subsets with sum k(dp)

Python/count_subsets_with_sum_k.py

@@ -0,0 +1,13 @@
+def findWays(nums, k):
+    MOD = 10**9 + 7
+    n = len(nums)
+
+    dp = [0] * (k + 1)
+    dp[0] = 1   # There is always 1 way to make sum = 0 (choose nothing)
+
+    for num in nums:
+        # Iterate backwards to avoid reusing the same element twice
+        for target in range(k, num - 1, -1):
+            dp[target] = (dp[target] + dp[target - num]) % MOD
+
+    return dp[k]