feat: adding Dasia's homework answers to Lesson 07

lesson_07/conditionals/src/lesson7.ts

@@ -7,7 +7,11 @@ import { computeLexicographicDistance } from "./util.js";
  * @return True if the age corresponds to a voting age and false otherwise.
  */
 export function canVote(age: number): boolean {
-  return false;
+  if (age >= 18) {
+    return true;
+  } else {
+    return false;
+  }
 }
 
 /**
@@ -18,13 +22,17 @@ export function canVote(age: number): boolean {
  * @return -1 if a is less than b, 1 if a is greater than b, and 0 otherwise.
  */
 export function compareStrings(a: string, b: string): number {
+  const distance = computeLexicographicDistance(a, b);
+
+  if (distance < 0) {
+    return -1;
+  }
+
+  return distance;
   // The distance will be a number less than 0 if string `a` is lexicographically less than `b`, 1
   // if it is greater, and 0 if the strings are equal.
-  const distance = computeLexicographicDistance(a, b);
 
   // TODO(you): Finish this method.
-
-  return 0;
 }
 
 /**
@@ -37,7 +45,30 @@ export function compareStrings(a: string, b: string): number {
  * @return The letter grade ("A+", "A", "A-", "B+", etc.).
  */
 export function convertGpaToLetterGrade(gpa: number): string {
-  return "F";
+  if (gpa < 0 || gpa > 4.0) {
+    return "Invaild GPA";
+  } else if (gpa < 1) {
+    return "F";
+  } else if (gpa < 1.3 && gpa >= 1.0) {
+    return "D";
+  } else if (gpa < 1.7 && gpa >= 1.3) {
+    return "D+";
+  } else if (gpa < 2.0 && gpa >= 1.7) {
+    return "C-";
+  } else if (gpa < 2.3 && gpa >= 2.0) {
+    return "C";
+  } else if (gpa < 2.7 && gpa >= 2.3) {
+    return "C+";
+  } else if (gpa < 3.0 && gpa >= 2.7) {
+    return "B-";
+  } else if (gpa < 3.3 && gpa >= 3.0) {
+    return "B";
+  } else if (gpa < 3.7 && gpa >= 3.3) {
+    return "B+";
+  } else if (gpa < 4.0 && gpa >= 3.7) {
+    return "A-";
+  }
+  return "A";
 }
 
 /**
@@ -47,17 +78,24 @@ export function convertGpaToLetterGrade(gpa: number): string {
  * @return The factorial of n.
  */
 export function computeFactorial(n: number): number {
-  return 0;
+  let sum = 1;
+  for (let i = 1; i <= n; i++) {
+    sum = sum *= i;
+  }
+  return sum;
 }
-
 /**
  * Adds all of the provided values and returns the sum.
  *
  * @param values The values to sum.
  * @return The sum of all the values.
  */
 export function addNumbers(values: number[]): number {
-  return 0;
+  let sum = 0;
+  for (const i of values) {
+    sum += i;
+  }
+  return sum;
 }
 
 /**
@@ -67,7 +105,18 @@ export function addNumbers(values: number[]): number {
  * @return An array containing the first `n` Fibonacci values.
  */
 export function getFirstNFibonacciNumbers(n: number): number[] {
-  return [];
+  let current = 1;
+  let prev = 0;
+
+  const numbers = [];
+
+  for (let i = 1; i <= n; i++) {
+    numbers.push(current);
+    const nextNumber = current + prev;
+    prev = current;
+    current = nextNumber;
+  }
+  return numbers;
 }
 
 /**
@@ -91,6 +140,13 @@ export function binarySearch(
   }
 
   const pivotIndex = Math.floor((start + end) / 2); // The index in the middle of the array.
+  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);
+  }
 
   // TODO(you): Finish implementing this algorithm