fibonacci, getTheTitles & findTheOldest excercise challenges

fibonacci/fibonacci.js

@@ -1,5 +1,11 @@
-const fibonacci = function() {
+const fibonacci = function (n) {
+  n = parseInt(n);
 
-}
+  let fib = [, 1, 1];
+  for (let i = 3; i <= n; i++) {
+    fib[i] = fib[i - 1] + fib[i - 2];
+  }
+  return n <= 0 ? "OOPS" : fib[n];
+};
 
-module.exports = fibonacci
+module.exports = fibonacci;

findTheOldest/findTheOldest.js

@@ -1,5 +1,28 @@
-let findTheOldest = function() {
+let findTheOldest = function (people) {
+  //   people.forEach((person) => {
+  //     this.lifeSpan =
+  //       person.yearOfDeath - person.yearOfBirth || Date("y") - person.yearOfBirth;
+  //   });
 
-}
+  return people.reduce((oldestPerson, currentPerson) => {
+    const oldestAge = getPersonAge(
+      oldestPerson.yearOfBirth,
+      oldestPerson.yearOfDeath
+    );
+    const currentAge = getPersonAge(
+      currentPerson.yearOfBirth,
+      currentPerson.yearOfDeath
+    );
 
-module.exports = findTheOldest
+    return currentAge > oldestAge ? currentPerson : oldestPerson;
+  });
+};
+
+const getPersonAge = (birthYear, deathYear) => {
+  if (!deathYear) {
+    deathYear = new Date().getFullYear();
+  }
+  return deathYear - birthYear;
+};
+
+module.exports = findTheOldest;

getTheTitles/getTheTitles.js

@@ -1,5 +1,9 @@
-const getTheTitles = function() {
-
+const getTheTitles = function(books) {
+    let titles = []
+    books.forEach(book => {
+        titles.push(book.title);
+    });
+    return titles
 }
 
 module.exports = getTheTitles;