From d2d829db0488c7a80b9cfa0550e871fd43adf347 Mon Sep 17 00:00:00 2001
From: Ashutosh Sharma <sharma.ashutosh0926@gmail.com>
Date: Sat, 24 Mar 2018 00:27:20 +0530
Subject: [PATCH] Create demonetization.c

Ways to dispense currency by ATM machine involving recursion.
---
 misc/demonetization.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 misc/demonetization.c

diff --git a/misc/demonetization.c b/misc/demonetization.c
new file mode 100644
index 00000000..b7bf8f10
--- /dev/null
+++ b/misc/demonetization.c
@@ -0,0 +1,24 @@
+// Recursion problem
+//Given the denominations of currencies available in a system, find the number of ways an ATM machine can
+//generate notes for an entered amount N.
+
+#include <stdio.h>
+
+int ways(int n, int a[], int k) {
+    if(n<0 || k<0) return 0;
+    if(n == 0) return 1;
+    if(k == 0) return 0;
+    return ways(n, a, k-1) + ways(n-a[k-1], a, k);
+}
+
+int main() {
+    int m; scanf("%d", &m);
+    int coin[m], i; for(i=0; i<m; i++) scanf("%d", &coin[i]);
+
+    int t; scanf("%d", &t);
+    while(t--) {
+        int n; scanf("%d", &n);
+        printf("%d\n", ways(n, coin, m));
+    }
+    return 0;
+}