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EternalEnvy · EternalEnvy · commit ac34d5d14788 · 2017-10-25T10:30:43.000-04:00
diff --git a/Algorithms/dynamic_programming/fibonacci.js b/Algorithms/dynamic_programming/fibonacci.js
@@ -1,3 +1,12 @@
+// Calculates fib(n) such that fib(n) = fib(n - 1) + fib(n - 2)
+// fib(0) = fib(1) = 1
+// Uses a bottom up dynamic programming approach
+// Solve each subproblem once, using results of previous subproblems,
+// which are n-1 and n-2 for Fibonacci numbers
+
+// Although this algorithm is linear in space and time as a function
+// of the input value n, it is exponential in the size of n as
+// a function of the number of input bits
 
 function fib(n) {
     var table = [];
@@ -6,9 +15,11 @@ function fib(n) {
     for (var i = 2; i < n; ++i) {
         table.push(table[i - 1] + table[i - 2]);
     }
-    console.log("The %dth fibonacci number is %d", n, table[n - 1]);
+    console.log("Fibonacci #%d = %d", n, table[n - 1]);
 }
 
+fib(1);
+fib(2);
 fib(200);
 fib(5);
 fib(10);
