added examples

ex3.c

@@ -0,0 +1,23 @@
+#include <tcclib.h>
+
+int fib(n)
+{
+    if (n <= 2)
+        return 1;
+    else
+        return fib(n-1) + fib(n-2);
+}
+
+int main(int argc, char **argv) 
+{
+    int n;
+    if (argc < 2) {
+        printf("usage: fib n\n"
+               "Compute nth Fibonacci number\n");
+        return 1;
+    }
+        
+    n = atoi(argv[1]);
+    printf("fib(%d) = %d\n", n, fib(n, 2));
+    return 0;
+}