Completion of Sprint 1

Author: Ayogit1

Sprint-1/fix/median.js

@@ -5,10 +5,30 @@
 // Hint: Please consider scenarios when 'list' doesn't have numbers (the function is expected to return null)
 // or 'list' has mixed values (the function is expected to sort only numbers).
 
+
 function calculateMedian(list) {
-  const middleIndex = Math.floor(list.length / 2);
-  const median = list.splice(middleIndex, 1)[0];
-  return median;
+  // chekc it is an rray
+  if (!Array.isArray(list)) return null;
+
+  // pull out numbers
+  const nums = list.filter(n => typeof n === "number" && !Number.isNaN(n));
+
+  // If no  numbers, return null
+  if (nums.length === 0) return null;
+
+  // Sort without changing original array
+  const sorted = [...nums].sort((a, b) => a - b);
+
+  const len = sorted.length;
+  const mid = Math.floor(len / 2);
+
+  //  If length is odd, take middle element
+  if (len % 2 === 1) {
+    return sorted[mid];
+  }
+
+  // If length is even  take average of two middle elements
+  return (sorted[mid - 1] + sorted[mid]) / 2;
 }
 
-module.exports = calculateMedian;
+module.exports = calculateMedian;

Sprint-1/implement/dedupe.js

@@ -1 +1,4 @@
-function dedupe() {}
+function dedupe(arr) {
+    // The spread operator [...] converts back to an array.
+    return [...new Set(arr)]; //New Set(arr) removes duplicates automatically
+}

Sprint-1/implement/max.js

@@ -1,4 +1,14 @@
-function findMax(elements) {
+
+function findMax(arr) {
+    // filter out non-numbers, non-numeric strings, and NaN. ALso convert string numbers to number
+    const numericValues = arr
+        .filter((item) => typeof item === "number" || (typeof item === "string" && item.trim() !== "" && !isNaN(item)))
+        .map((item) => Number(item));
+
+    // returns -Infinity i no numerical elements are found
+    if (numericValues.length === 0) return -Infinity;
+
+    return Math.max(...numericValues);
 }
 
 module.exports = findMax;

Sprint-1/implement/sum.js

@@ -1,4 +1,11 @@
-function sum(elements) {
+sum.js
+function sum(arr) {
+    return arr.reduce((accumulator, currentValue) => {
+        if (typeof currentValue === 'number' && !isNaN(currentValue)) {  // investigate  if the current element is a number and not NaN
+            return accumulator + currentValue;
+        }
+        return accumulator;  // If not a number, return current sum
+    }, 0); // This line initialize sum at 0 for  empty arrays
 }
 
 module.exports = sum;