tabulated code in python for coin change problem added

Author: shvbsle

coin_change.py

@@ -0,0 +1,40 @@
+'''
+DYnamic Programming: Coing Change problem
+
+Given a value N, if we want to make change for N cents, and we have infinite supply of each of S = { S1, S2, .. , Sm} valued coins, how many ways can we make the change? The order of coins doesn’t matter.
+
+
+Input Format:
+4
+1 2 3
+
+the first line is the change
+and second lines contain denominations (D)
+
+Algorithm Strategy:
+
+N(val) = sum{ N(r) + N(val - r) for r in D }
+
+'''
+
+N = int(input())
+D = list(map(int, input().split(" ")))
+m = {}
+
+def solve(d, Dd):
+	if (d, len(Dd)) in m:
+		return m[(d, len(Dd))]
+	ans = 0
+	if d == 0:
+		return 1
+	if d < 0:
+		return 0
+	if len(Dd) <= 0 and d >=1:
+		return 0
+	#----no .of ways to get to d using sub arrays + number of ways to get to d-r uring D
+	ans = solve(d, Dd[:len(Dd)-1])            +       solve(d - Dd[len(Dd)-1], Dd)
+	m[(d, len(Dd))] = ans
+	return ans
+
+print(solve(4, D))
+

ip.txt

@@ -1 +1,2 @@
-1 5 8 9 10 17 17 20
+4
+1 2 3