dynamic programming approach of fibonacci series

algorithms/JavaScript/src/index.js

@@ -7,6 +7,8 @@ require('./linked-lists/singly');
 
 // Maths
 require('./maths/fibonacci-series');
+require('./maths/dynamic-fibonacci-series');
+
 
 // Recursion
 require('./recursion/factorial');

algorithms/JavaScript/src/maths/dynamic-fibonacci-series.js

@@ -0,0 +1,30 @@
+// dynamic programming approach of fibonacci series 
+// time complexity: O(n)
+
+function dynamicFibonacci() {
+  let cache = {};
+  
+  // here is the concept of closure in javaScript
+  const fib = (n) => {
+      // check if already calculated for n
+      if (n in cache) {
+          return cache[n];
+      } else if (n < 2) { // base case
+          return n;
+      } else {
+          // store result in cache
+          cache[n] = fib(n - 1) + fib(n - 2);
+          return cache[n];
+      }
+  }
+ console.log(fib(10));
+}
+dynamicFibonacci();
+// output: 55
+
+
+
+
+
+
+