From 739a00d34a1755396ccd66c1277dc242615f9957 Mon Sep 17 00:00:00 2001
From: Nilay Lilawala <nilay.lilawala@gmail.com>
Date: Fri, 15 Oct 2021 12:15:51 +0530
Subject: [PATCH] Modified main.c file of Factorial_using_recursion, made it
 more user-friendly.

---
 .../007_Factorial_using_recursion/main.c      | 23 ++++++++++++-------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/001_RECURSION/007_Factorial_using_recursion/main.c b/001_RECURSION/007_Factorial_using_recursion/main.c
index f4c59fe..9ec5b18 100644
--- a/001_RECURSION/007_Factorial_using_recursion/main.c
+++ b/001_RECURSION/007_Factorial_using_recursion/main.c
@@ -3,26 +3,33 @@
 
 int factorial(int n)
 {
-    if(n>1)
+    if(n == 0 || n == 1)
     {
-        return n * factorial(n-1);
+        return 1;
     }
-    else if (n>=0)
+    else if (n>1)
     { 
-        return 1;
+        return n * factorial(n-1);
     }
     else
     {
-        exit(-1);
+        return -1;
     }
 }
 
 int main()
 {
     int n;
+    printf("Enter a non-negative number : ");
     scanf("%d", &n);
-
-    printf("Factorial of %d is : %d", n, factorial(n));
+    if(factorial(n) == -1)
+    {
+	printf("%d is a negative number. Factorial doesn't exist for a negative number!\n", n);
+    }
+    else
+    {
+	printf("Factorial of %d is : %d", n, factorial(n));
+    }
 
     return 0;
-}
\ No newline at end of file
+}