Fundamental's Follow up Projects › Capstone Project

Project 3 — Expense & Budget Tracker

Capstone Project 40 minTally spending by category, compare against budgets, and report

Your task

Build monthly_report(expenses, budgets): tally spend per category, then return {"total", "by_category", "over": sorted categories over their budget, "top": the biggest-spend category (or None)}.

Project 3 — Expense & Budget Tracker

A money app in miniature. Log expenses by category, compare spend against budgets, and surface what matters: total, per-category breakdown, over-budget alerts, and your biggest spending category.

Build the four steps, then assemble monthly_report(expenses, budgets).

Step 1 — add_up: total all expenses.
Step 2 — by_category: {category: total}.
Step 3 — over_budget: which categories blew their limit.
Step 4 — top_category: the biggest spender.

Skills: dict tallying with .get, comprehensions, sorted, max(key=…), guards.

Practice — level up

0/4 solved

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BuildStep 1 — Total spend

An expense is {"category": str, "amount": number}. Write add_up(expenses) returning the total amount.

dict-accesssum

BuildStep 2 — Group by category

Write by_category(expenses) returning {category: total_spent}.

setdefault/getloop

BossStep 3 — Over budget

Given spent {category: amount} and budgets {category: limit}, write over_budget(spent, budgets) returning the sorted categories whose spend exceeds their limit. A category with no budget is never over.

dictcomprehensionsorted

BossStep 4 — Biggest category

Write top_category(expenses) returning the category with the highest total spend (or None if empty).

groupmax-keyguard

monthly_report(expenses, budgets) → dictTally spending by category, compare against budgets, and report

expenses : list

budgets : dict

try:

returned

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