Update expenditure-analysis.js

01-js/easy/expenditure-analysis.js

@@ -8,8 +8,27 @@
   - `npm run test-expenditure-analysis`
 */
 
+// This function calculates the total amount spent by category in the transactions
 function calculateTotalSpentByCategory(transactions) {
-  return [];
+  let temp = {};
+  for (let i = 0; i < transactions.length; i++) {
+    var t = transactions[i];
+    if (temp[t.category]) {
+      temp[t.category] = (temp[t.category] + t.price);
+    } else {
+      temp[t.category] = (t.price);
+    }
+  }
+  let keys = Object.keys(temp);
+
+  let ans = [];
+  for (let i = 0; i < keys.length; i++) {
+    let t = keys[i];
+    ans.push({ category: t, totalSpent: temp[t] });
+  }
+  // Uncomment the line below to see the result
+  // console.log(ans);
+  return ans;
 }
 
 module.exports = calculateTotalSpentByCategory;