Loops Exercises

Author: Lbeckap

loops/exercises/for-Loop-Exercises.js

@@ -4,21 +4,66 @@
     c. Print the EVEN numbers 12 to -14 in descending order, one number per line.
     d. Challenge - Print the numbers 50 - 20 in descending order, but only if the numbers are multiples of 3. (Your code should work even if you replace 50 or 20 with other numbers). */
 
+for (let i = 0; i < 21; i++) {
+  console.log(i);
+}
 
+//i starts at 3, i += 2 counts upward adding 2, therefore i would be 3, 5, 7, etc..
+for (let i = 3; i < 30; i+=2) {
+  console.log(i);
+}
 
+//i starts at 12, i -= 2 counts downward subracting 2, therefore i would be 12, 10, 8, etc..
+for (let i = 12; i > -15; i-=2) {
+    console.log(i);
+}
+
+for (let i = 50; i > 19; i--) {
+  if (i % 3 === 0) {
+    console.log(i);
+  }
+}
+//OR Another possible way is below...
+//How to stop from printing the first iteration of 50? Maybe not possible in this syntax because the initial expression executes once before any loop interations.
+for (let i = 50; i > 19; i -= 2 + (i % 3 === 0)) {
+    console.log('.',i);
+}
 
 /*Exercise #2: 
+
 Initialize two variables to hold the string “LaunchCode” and the array [1, 5, ‘LC101’, ‘blue’, 42].
 
 
 Construct ``for`` loops to accomplish the following tasks:
   a. Print each element of the array to a new line.
   b. Print each character of the string - in reverse order - to a new line. */ 
 
+let str = "LaunchCode";
+let arr = [1, 5, 'LC101', 'blue', 42];
 
+for (let i = str.length - 1; i >= 0; i--) {
+  console.log(str[i]);
+}
 
-
+for (let i = 0; i < arr.length; i++) {
+  console.log(arr[i]);
+}
 
 /*Exercise #3:Construct a for loop that sorts the array [2, 3, 13, 18, -5, 38, -10, 11, 0, 104] into two new arrays:
   a. One array contains the even numbers, and the other holds the odds.
-  b. Print the arrays to confirm the results. */
+  b. Print the arrays to confirm the results. */
+ let arrNum = [2, 3, 13, 18, -5, 38, -10, 11, 0, 104];
+ let evens = [];
+ let odds = [];
+
+for (let i = 0; i < arrNum.length; i++) {
+  if (arrNum[i] % 2 === 0) {
+    evens.push(arrNum[i]);
+  } else {
+    odds.push(arrNum[i]);
+  }
+}
+
+console.log(evens);
+console.log(odds);
+