ITP LONDON_JAN 2025 | SAMUNTA SUNUWAR | MODULE DATA GROUPS| SPRINT 1

Sprint-1/fix/median.js

@@ -3,9 +3,15 @@
 // If you're in the Sprint-1 directory, you can run `npm test -- fix` to run the tests in the fix directory
 
 function calculateMedian(list) {
-  const middleIndex = Math.floor(list.length / 2);
-  const median = list.splice(middleIndex, 1)[0];
-  return median;
+  const arrLength = list.length;
+  const middleIndex = Math.floor(arrLength / 2);
+  if (arrLength % 2 === 0) {
+    const num2 = list[middleIndex - 1];
+    const num1 = list[middleIndex];
+    return (num1 + num2) / 2;
+  } else {
+    return list[middleIndex];
+  }
 }
 
 module.exports = calculateMedian;

Sprint-1/fix/median.test.js

@@ -15,6 +15,7 @@ describe("calculateMedian", () => {
   test("returns the average of middle values for even length array", () => {
     expect(calculateMedian([1, 2, 3, 4])).toEqual(2.5);
     expect(calculateMedian([1, 2, 3, 4, 5, 6])).toEqual(3.5);
+    expect(calculateMedian([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])).toEqual(5.5);
   });
 
   test("doesn't modify the input", () => {

Sprint-1/implement/dedupe.js

@@ -1 +1,29 @@
-function dedupe() {}
+// function dedupe(arr) {
+//   const uniqueArray = [];
+
+//   for (let i = 0; i < arr.length; i++) {
+//     let isDuplicate = false;
+
+//     // iterates over uniqueArray and checks if arr[i] is in that array
+//     for (let j = 0; j < uniqueArray.length; j++) {
+//       if (arr[i] === uniqueArray[j]) {
+//         isDuplicate = true;
+//       }
+//     }
+
+//     // if arr[i] is not already in uniqueArray, add it to uniqueArray
+//     if (isDuplicate === false) {
+//       uniqueArray.push(arr[i]);
+//     }
+//   }
+
+//   return uniqueArray;
+// }
+// Refactored code using SET
+function dedupe(arr) {
+  return [...new Set(arr)]; // Convert Set back to an array
+}
+
+console.log(dedupe([1, 2, 3, 3, 4, 4, 5, 8, 8]));
+
+module.exports = dedupe;

Sprint-1/implement/dedupe.test.js

@@ -21,7 +21,29 @@ test.todo("given an empty array, it returns an empty array");
 // Given an array with no duplicates
 // When passed to the dedupe function
 // Then it should return a copy of the original array
+test.todo("given an array with no duplicates, it returns original array");
 
 // Given an array with strings or numbers
 // When passed to the dedupe function
 // Then it should remove the duplicate values, preserving the first occurence of each element
+test.todo(
+  "given an array with duplicates, removes duplicate preserving the first occurence of each element"
+);
+
+describe("dedupe", () => {
+  test("given an empty array, it returns an empty array", () => {
+    expect(dedupe([])).toEqual([]);
+  });
+
+  test("given an array with no duplicates, it returns original array", () => {
+    expect(dedupe([1, 2, 3, 4])).toEqual([1, 2, 3, 4]);
+    expect(dedupe(["c", "a", "t"])).toEqual(["c", "a", "t"]);
+    expect(dedupe([1, 2, 11])).toEqual([1, 2, 11]);
+  });
+
+  test("removes duplicates from an array", () => {
+    expect(dedupe(["a", "a", "a", "b", "b", "c"])).toEqual(["a", "b", "c"]);
+    expect(dedupe([5, 1, 1, 2, 3, 2, 5, 8])).toEqual([5, 1, 2, 3, 8]);
+    expect(dedupe([1, 2, 1])).toEqual([1, 2]);
+  });
+});

Sprint-1/implement/max.js

@@ -1,4 +1,28 @@
+// function findMax(elements) {
+//   if (elements.length === 0) {
+//     return -Infinity;
+//   }
+
+//   let max = -Infinity;
+
+//   for (let i = 0; i < elements.length; i++) {
+//     if (typeof elements[i] === "number" && !isNaN(elements[i])) {
+//       if (elements[i] > max) {
+//         max = elements[i];
+//       }
+//     }
+//   }
+
+//   return max;
+// }
+
+//Refactored code using Math.max
 function findMax(elements) {
+  const validNumbers = elements.filter(
+    (num) => typeof num === "number" && !isNaN(num)
+  );
+
+  return validNumbers.length ? Math.max(...validNumbers) : -Infinity;
 }
 
 module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -21,23 +21,73 @@ test.todo("given an empty array, returns -Infinity");
 // Given an array with one number
 // When passed to the max function
 // Then it should return that number
+test.todo("given an array with one number, returns that number");
 
 // Given an array with both positive and negative numbers
 // When passed to the max function
 // Then it should return the largest number overall
+test.todo(
+  "given an array with positive and negative number, returns the largest number overall"
+);
 
 // Given an array with just negative numbers
 // When passed to the max function
 // Then it should return the closest one to zero
+test.todo(
+  "given an array with negative number, returns the largest number which is closest to 0"
+);
 
 // Given an array with decimal numbers
 // When passed to the max function
 // Then it should return the largest decimal number
-
+test.todo(
+  "given an array with decimal numbers, returns the largest decimal number"
+);
 // Given an array with non-number values
 // When passed to the max function
 // Then it should return the max and ignore non-numeric values
-
+test.todo(
+  "given an array with non-number values, returns the max and ignore non-numeric values"
+);
 // Given an array with only non-number values
 // When passed to the max function
 // Then it should return the least surprising value given how it behaves for all other inputs
+test.todo(
+  "given an array with non-number values, returns the least surprising value"
+);
+
+describe("findMax function", () => {
+  test("given an empty array, returns -Infinity", () => {
+    expect(findMax([])).toEqual(-Infinity);
+  });
+
+  test("given an array with one number, returns that number", () => {
+    expect(findMax([5])).toEqual(5);
+    expect(findMax([-10])).toEqual(-10);
+  });
+
+  test("given an array with positive and negative numbers, returns the largest number overall", () => {
+    expect(findMax([-1, 2, 3, -10])).toEqual(3);
+    expect(findMax([-100, 0, 50, -200])).toEqual(50);
+  });
+
+  test("given an array with negative numbers, returns the largest number which is closest to 0", () => {
+    expect(findMax([-5, -2, -8, -10])).toEqual(-2);
+    expect(findMax([-100, -50, -1, -20])).toEqual(-1);
+  });
+
+  test("given an array with decimal numbers, returns the largest decimal number", () => {
+    expect(findMax([1.5, 2.7, 3.9, 3.8])).toEqual(3.9);
+    expect(findMax([-1.1, -0.5, -0.9])).toEqual(-0.5);
+  });
+
+  test("given an array with non-number values, returns the max and ignores non-numeric values", () => {
+    expect(findMax([5, "a", null, 10, undefined, 3])).toEqual(10);
+    expect(findMax(["hello", 2, {}, 7, NaN, 1])).toEqual(7);
+  });
+
+  test("given an array with only non-number values, returns the least surprising value", () => {
+    expect(findMax(["a", {}, null, undefined])).toEqual(-Infinity);
+    expect(findMax([NaN, "hello", {}])).toEqual(-Infinity);
+  });
+});

Sprint-1/implement/sum.js

@@ -1,4 +1,12 @@
 function sum(elements) {
-}
+  let total = 0;
 
+  for (let i = 0; i < elements.length; i++) {
+    if (typeof elements[i] === "number" && !isNaN(elements[i])) {
+      total += elements[i];
+    }
+  }
+  //   return total;
+  return Number(total.toFixed(2)); // to avoid getting lot of decimal points for sum of floating number
+}
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -13,24 +13,65 @@ const sum = require("./sum.js");
 // Given an empty array
 // When passed to the sum function
 // Then it should return 0
-test.todo("given an empty array, returns 0")
+test.todo("given an empty array, returns 0");
 
 // Given an array with just one number
 // When passed to the sum function
 // Then it should return that number
+test.todo("given an array with just one number, return that number");
 
 // Given an array containing negative numbers
 // When passed to the sum function
 // Then it should still return the correct total sum
+test.todo("given an array with negative numbers, return correct total sum");
 
 // Given an array with decimal/float numbers
 // When passed to the sum function
 // Then it should return the correct total sum
+test.todo(
+  "given an array with decimal/float numbers, return correct total sum"
+);
 
 // Given an array containing non-number values
 // When passed to the sum function
 // Then it should ignore the non-numerical values and return the sum of the numerical elements
+test.todo(
+  "given an array containing non-number values, ignore non numeric and return correct total sum for numerical elements"
+);
 
 // Given an array with only non-number values
 // When passed to the sum function
 // Then it should return the least surprising value given how it behaves for all other inputs
+test.todo(
+  "given an array with only number values, return the least surprising value given how it behaves for all other inputs"
+);
+
+describe("sum", () => {
+  test("given an empty array, returns 0", () => {
+    expect(sum([])).toEqual(0);
+  });
+
+  test("given an array with just one number, return that number", () => {
+    expect(sum([5])).toEqual(5);
+    expect(sum([-3])).toEqual(-3);
+  });
+
+  test("given an array with negative numbers, return correct total sum", () => {
+    expect(sum([-1, -2, -3])).toEqual(-6);
+    expect(sum([-10, 5, -5])).toEqual(-10);
+  });
+
+  test("given an array with decimal/float numbers, return correct total sum", () => {
+    expect(sum([1.5, 2.5, 3.5])).toEqual(7.5);
+    expect(sum([-1.1, -2.2, 3.3])).toBeCloseTo(0); //using to be close to to fix issue with unpredicted decimal points
+  });
+
+  test("given an array containing non-number values, ignore non numeric and return correct total sum for numerical elements", () => {
+    expect(sum([1, "a", 2, null, 3])).toEqual(6);
+    expect(sum([true, false, 4, "5", 6])).toEqual(10);
+  });
+
+  test("given an array with only non-number values, return the least surprising value given how it behaves for all other inputs", () => {
+    expect(sum(["a", true, null, undefined])).toEqual(0);
+  });
+});

Sprint-1/refactor/includes.js

@@ -1,8 +1,19 @@
 // Refactor the implementation of includes to use a for...of loop
 
+// function includes(list, target) {
+//   for (let index = 0; index < list.length; index++) {
+//     const element = list[index];
+//     if (element === target) {
+//       return true;
+//     }
+//   }
+//   return false;
+// }
+
+//Refactored code
+
 function includes(list, target) {
-  for (let index = 0; index < list.length; index++) {
-    const element = list[index];
+  for (const element of list) {
     if (element === target) {
       return true;
     }