Added new algorithm in C/recursion

algorithms/C/recursion/factorial-of-number.c

@@ -0,0 +1,27 @@
+/*
+Factorial of the number: Factorial of a non-negative integer is the multiplication of all positive integers smaller than or equal to n.
+For example factorial of 6 is 6*5*4*3*2*1 which is 720.
+  Input    |    Output
+  5        |    120
+  6        |    720
+  3        |    6
+Time Complexity - O(log(n))
+Space Complexity- O(1)
+
+*/
+#include<stdio.h>
+int fact(int n){
+	if(n==1){
+		return 1;
+	}
+	else{
+		return n*fact(n-1);
+	}
+}
+void main(){
+	int an;
+	printf("Enter a number");
+	scanf("%d",&an);
+	int f=fact(an);
+	printf("factorial of %d is %d",an,f);
+}