@@ -34,6 +34,7 @@ public static long FastFib(int N, HashMap<Integer, Long> cache) {
3434 }
3535}
3636
37+ 3738public class PracticeAlgorithms {
3839 public static boolean isBetweenZeroAndOne (double x , double y ) {
3940 return (0 < x && x < 1 ) && (0 < y && y < 1 );
@@ -112,7 +113,7 @@ public static int[][] matrixTransposition(int[][] theMatrix) {
112113
113114
114115 /**
115- * recursive method that returns the greatest integer not greater than log(N)
116+ * static recursive method that returns the greatest integer not greater than log(N)
116117 * to base two
117118 * */
118119 public static int lg (int N ) {
@@ -121,6 +122,15 @@ public static int lg(int N) {
121122 return 1 + lg (N / 2 );
122123 }
123124
125+ /**
126+ * static recursive method to compute the factorial of an integer "N"
127+ * */
128+ public static long fact (int N ) {
129+ if (N == 1 ) return 1 ;
130+ 131+ return N * fact (N - 1 );
132+ }
133+ 124134
125135 public static void main (String [] args ) {
126136 Random generator = new Random ();
@@ -165,17 +175,19 @@ public static void main(String[] args) {
165175
166176 // loop utilizing dynamic programming and memoization
167177 System .out .println ("- Dynamic Programming and Memoization" );
168- for (int i = 0 ; i <= 80 ; i ++) {
178+ for (int i = 0 ; i <= 40 ; i ++) {
169179 System .out .println (Fibonacci .FastFib (i , cache ));
170180 }
171181 System .out .println ();
172182
173- // loop utilizing the recursive fib method
174- System .out .println ("- Recursion" );
175- for (int i = 0 ; i <= 80 ; i ++) {
176- System .out .println (Fibonacci .Fib (i ));
177- }
178- System .out .println ();
183+ // loop utilizing the recursive fib method
184+ System .out .println ("- Recursion" );
185+ for (int i = 0 ; i <= 40 ; i ++) {
186+ System .out .println (Fibonacci .Fib (i ));
187+ }
188+ System .out .println ();
179189
190+ System .out .printf ("31!: %d\n " , fact (31 )); // N > 31 causes overflow
191+ System .out .println ();
180192 }
181193}
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