diff --git a/lesson_07/conditionals/src/lesson7.ts b/lesson_07/conditionals/src/lesson7.ts index 52f45df8b..62cf8ea16 100644 --- a/lesson_07/conditionals/src/lesson7.ts +++ b/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; + } } /** @@ -21,10 +25,13 @@ export function compareStrings(a: string, b: string): number { // 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; + if (distance < 0) { + return -1; + } else if (distance > 0) { + return 1; + } else { + return 0; + } } /** @@ -37,7 +44,29 @@ 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 === 4.0) { + return "A"; + } else if (gpa >= 3.7) { + return "A-"; + } else if (gpa >= 3.3) { + return "B+"; + } else if (gpa >= 3.0) { + return "B"; + } else if (gpa >= 2.7) { + return "B-"; + } else if (gpa >= 2.3) { + return "C+"; + } else if (gpa >= 2.0) { + return "C"; + } else if (gpa >= 1.7) { + return "C-"; + } else if (gpa >= 1.3) { + return "D+"; + } else if (gpa >= 1.0) { + return "D"; + } else { + return "F"; + } } /** @@ -47,7 +76,11 @@ export function convertGpaToLetterGrade(gpa: number): string { * @return The factorial of n. */ export function computeFactorial(n: number): number { - return 0; + let result = 1; + for (let i = 1; i <= n; i++) { + result *= i; + } + return result; } /** @@ -57,7 +90,11 @@ export function computeFactorial(n: number): number { * @return The sum of all the values. */ export function addNumbers(values: number[]): number { - return 0; + let total = 0; + for (const value of values) { + total += value; + } + return total; } /** @@ -67,7 +104,18 @@ export function addNumbers(values: 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]; + } + const fibonacciSequence: number[] = [1, 1]; + for (let i = 2; i < n; i++) { + const newNumber = fibonacciSequence[i - 1] + fibonacciSequence[i - 2]; + fibonacciSequence.push(newNumber); + } + return fibonacciSequence.slice(0, n); } /** @@ -90,13 +138,12 @@ export function binarySearch( return -1; } - const pivotIndex = Math.floor((start + end) / 2); // The index in the middle of the array. - - // TODO(you): Finish implementing this algorithm - - // If values[pivotIndex] is equal to value then return `pivotIndex`. - // 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; + const pivotIndex = Math.floor((start + end) / 2); + 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); + } }