feat: simple recursion

app-ch4-18.js

@@ -0,0 +1,32 @@
+// Time O(n^2)
+function fibonacciSequence(n){
+    if(n===0) return 0
+    if(n===1) return 1
+
+    return fibonacciSequence(n - 1) + fibonacciSequence(n-2)
+}
+
+for(let i=0; i<=15; i++){
+    console.log(`fibonacciSequence - ${i} :`, fibonacciSequence(i))
+}
+
+// Time O(n)
+function fib(n){
+    const resultArr = Array.from({ length: n })
+
+    resultArr[0] = 0
+    resultArr[1] = 1
+
+    if (n === 0) return resultArr[0]
+    if (n === 1) return resultArr[1]
+
+    for (let i = 2; i <= n; i++) {
+        resultArr[i] = resultArr[i - 1] + resultArr[i - 2]
+    }
+
+    return resultArr[n]
+};
+
+for (let i = 0; i <= 15; i++) {
+    console.log(`fib - ${i} :`, fib(i))
+}

app-ch4-19.js

@@ -0,0 +1,11 @@
+const arrs = [[[["a", [["b", ["c"]], ["d"]]], [["e"]], [[["f", "g", "h"]]]]]]
+const result = []
+
+function collector(rawData){
+    for (let i = 0; i < rawData.length; i++) {
+        Array.isArray(rawData[i]) ? collector(rawData[i]) : result.push(rawData[i])
+    }
+}
+collector(arrs)
+
+console.log('after using collector:', result)