chore(C): add fibonacci series (#666)

algorithms/C/README.md

@@ -32,6 +32,7 @@
 ## Maths
 
 - [Palindrome Number](maths/palindrome.c)
+- [Fibonacci Series](maths/fibonacci-series.c)
 
 ## Queues
 

algorithms/C/maths/fibonacci-series.c

@@ -0,0 +1,35 @@
+/**
+     *   The Fibonacci Sequence is the series of numbers:
+     *
+     *   0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ...
+     *
+     *   The next number is found by adding up the two numbers before it:, next number is the sum of previous two numbers
+     *   for example 0,
+     *   1, 1, 2, 3, 5, 8, 13, 21 etc. 
+     *   The first two numbers of fibonacci series are 0 and 1.
+     *   Time complexity: O(n)
+* */
+
+#include <stdio.h>
+
+void fibonacci(int n)
+{
+    int a = 0, b = 1, c = 0;
+    printf("%d %d ", a, b);     // print 0 1
+    for (int i = 2; i < n; i++) //loop starts from 2 because 0 and 1 are already printed
+    {
+        c = a + b;
+        printf("%d ", c);
+        a = b;
+        b = c;
+    }
+}
+
+int main()
+{
+    int n;
+    printf("Enter the number of terms: ");
+    scanf("%d", &n);
+    fibonacci(n);
+    return 0;
+}