feat: adds Tyran's Lesson 07 and Part D functions

lesson_07/conditionals/.env.test

@@ -1 +1 @@
-HW_VERSION=your homework version here
+HW_VERSION=D

lesson_07/conditionals/src/lesson7.ts

@@ -12,7 +12,11 @@ export function compareStrings(a: string, b: string): number {
   // if it is greater, and 0 if the strings are equal.
   const distance = computeLexicographicDistance(a, b);
 
-  // TODO(you): Finish this method.
+  if (distance < 0) {
+    return -1;
+  } else if (distance > 0) {
+    return 1;
+  }
 
   return 0;
 }
@@ -24,7 +28,15 @@ export function compareStrings(a: string, b: string): number {
  * @return The factorial of n.
  */
 export function computeFactorial(n: number): number {
-  return 0;
+  if (n < 0) return 0;
+  if (n === 0) return 1;
+
+  let result = n;
+  for (let i = n - 1; i >= 1; i--) {
+    result *= i;
+  }
+
+  return result;
 }
 
 /**
@@ -34,7 +46,16 @@ export function computeFactorial(n: number): number {
  * @return An array containing the first `n` Fibonacci values.
  */
 export function getFirstNFibonacciNumbers(n: number): number[] {
-  return [];
+  if (n === 0) return [];
+  if (n === 1) return [1];
+  if (n === 2) return [1, 1];
+
+  const fibArr: number[] = [1, 1];
+  for (let i = 2; i < n; i++) {
+    fibArr.push(fibArr[i - 1] + fibArr[i - 2]);
+  }
+
+  return fibArr;
 }
 
 /**
@@ -65,5 +86,9 @@ export function binarySearch(
   // Else if values[pivotIndex] is greater than the value, then
   // call `binarySearch(values, start, pivotIndex - 1, value)` and return its value;
   // Else call `binarySearch(values, pivotIndex + 1, end, value)` and return its value.
-  return -1;
+
+  if (values[pivotIndex] === value) return pivotIndex;
+  else if (values[pivotIndex] > value)
+    return binarySearch(values, start, pivotIndex - 1, value);
+  else return binarySearch(values, pivotIndex + 1, end, value);
 }

lesson_07/conditionals/src/part_d.ts

@@ -7,7 +7,7 @@
  * @returns
  */
 export function isWithinRange(num: number, min: number, max: number): boolean {
-  return false;
+  return num >= min && num <= max;
 }
 
 /**
@@ -19,7 +19,7 @@ export function isWithinRange(num: number, min: number, max: number): boolean {
  * @returns
  */
 export function isValidTriangle(a: number, b: number, c: number): boolean {
-  return false;
+  return Math.pow(a, 2) + Math.pow(b, 2) === Math.pow(c, 2);
 }
 
 /**
@@ -30,5 +30,15 @@ export function isValidTriangle(a: number, b: number, c: number): boolean {
  * @returns
  */
 export function getSeason(month: number): string {
+  if (month >= 3 && month <= 5) {
+    return "Spring";
+  } else if (month >= 6 && month <= 8) {
+    return "Summer";
+  } else if (month >= 9 && month <= 11) {
+    return "Fall";
+  } else if (month === 12 || month === 1 || month === 2) {
+    return "Winter";
+  }
+
   return "Invalid month";
 }