diff --git a/problems/medium/m13.py b/problems/medium/m13.py
index 33dfa3f..fad945b 100644
--- a/problems/medium/m13.py
+++ b/problems/medium/m13.py
@@ -1,15 +1,9 @@
 '''
 Create a program that checks whether a given number is a prime number or not.
 '''
-def is_prime(num):
-    if num < 2:
-        return False
-    for i in range(2, num):
-        if num % i == 0:
-            return False
-    return True
+a=int(input("Enter Number:"))
 
-n = int(input("Enter a number: "))
-for i in range(2, n + 1):
-    if is_prime(i):
-        print(i)
+if (a%2==0 or a%3==0) and a/2>=2:
+    print(a,"is not a Prime Number")
+else:
+    print(a,"is a Prime Number")
\ No newline at end of file
diff --git a/problems/medium/m15.py b/problems/medium/m15.py
index afcb2e3..1a0b30c 100644
--- a/problems/medium/m15.py
+++ b/problems/medium/m15.py
@@ -11,6 +11,6 @@ def Arms(a):
 b=Arms(a)
 f=int(a)
 if b==f:
-   print(b,"is an Armstrong Number")
+   print(f,"is an Armstrong Number")
 else:
-   print(b,"is not An Armstrong Number")
\ No newline at end of file
+   print(f,"is not An Armstrong Number")
\ No newline at end of file