diff --git a/app.js b/app.js
deleted file mode 100644
index ad9a93a7..00000000
--- a/app.js
+++ /dev/null
@@ -1 +0,0 @@
-'use strict';
diff --git a/fib.js b/fib.js
new file mode 100644
index 00000000..28707bff
--- /dev/null
+++ b/fib.js
@@ -0,0 +1,19 @@
+'use strict';
+console.time('fib');
+const memo = new Map();
+memo.set(0, 0);
+memo.set(1, 0);
+memo.set(2, 1);
+function fib(n){
+  if(memo.has(n)){
+    return memo.get(n);
+  }
+  const v = fib(n - 1) + fib(n - 2);
+  memo.set(n, v);
+  return v;
+}
+let l = process.argv[2] || 10;
+for(let i = 0; i <= l; i++){
+  console.log(fib(i));
+}
+console.timeEnd('fib');
\ No newline at end of file
diff --git a/trib.js b/trib.js
new file mode 100644
index 00000000..67cf240f
--- /dev/null
+++ b/trib.js
@@ -0,0 +1,19 @@
+'use strict';
+console.time('trib');
+const memo = new Map();
+memo.set(0, 0);
+memo.set(1, 0);
+memo.set(2, 1);
+function trib(n){
+  if(memo.has(n)){
+    return memo.get(n);
+  }
+  const v = trib(n - 1) + trib(n - 2) + trib(n - 3);
+  memo.set(n, v);
+  return v;
+}
+let l = process.argv[2] || 10;
+for(let i = 0; i <= l; i++){
+  console.log(trib(i));
+}
+console.timeEnd('trib');
\ No newline at end of file