Leetcode problem : Fruit Basket

app.js

@@ -1,132 +1,110 @@
-const express = require('express');
-const mongoose = require('mongoose');
-const bcrypt = require('bcrypt');
-const cors = require('cors');
-
-// Import required modules
-
-// Create an Express app
-const app = express();
-
-// Enable CORS
-app.use(express.json());
-app.use(cors());
-
-// Connect to MongoDB
-mongoose.connect('mongodb://localhost:27017/cafe', { useNewUrlParser: true, useUnifiedTopology: true })
-    .then(() => {
-        console.log('Connected to MongoDB');
-    })
-    .catch((error) => {
-        console.error('Error connecting to MongoDB:', error);
-    });
-
-// Define a user schema
-const userSchema = new mongoose.Schema({
-    username: { type: String, required: true },
-    password: { type: String, required: true }
-});
-
-// Define a user model
-const User = mongoose.model('User', userSchema);
-const productSchema = new mongoose.Schema({
-    name: { type: String, required: true },
-    price: { type: Number, required: true },
-    quantity: { type: Number, required: true }
-});
-const Product = mongoose.model('Product', productSchema);
-// Register a new user
-app.post('/register', async (req, res) => {
-    try {
-        const { username, password } = req.body;
-
-        // Check if the username already exists
-        const existingUser = await User.findOne({ username });
-        if (existingUser) {
-            return res.status(400).json({ message: 'Username already exists' });
-        }
-
-        // Hash the password
-        const hashedPassword = await bcrypt.hash(password, 10);
-
-        // Create a new user
-        const newUser = new User({ username, password: hashedPassword });
-        await newUser.save();
-
-        res.status(201).json({ message: 'User registered successfully' });
-    } catch (error) {
-        console.error('Error registering user:', error);
-        res.status(500).json({ message: 'Internal server error' });
-    }
-});
-
-// User login
-app.post('/login', async (req, res) => {
-    try {
-        const { username, password } = req.body;
-
-        // Find the user by username
-        const user = await User.findOne({ username });
-        if (!user) {
-            return res.status(404).json({ message: 'User not found' });
-        }
-
-        // Compare the password
-        const isPasswordValid = await bcrypt.compare(password, user.password);
-        if (!isPasswordValid) {
-            return res.status(401).json({ message: 'Invalid password' });
-        }
-
-        res.status(200).json({ message: 'Login successful' });
-    } catch (error) {
-        console.error('Error logging in:', error);
-        res.status(500).json({ message: 'Internal server error' });
-    }
-});
-
-app.get('/products',async (req,res)=>{
-    try{
-        const products = await Product.find();
-        res.status(200).json(products);
-    }catch(error){
-        console.error('Error getting products:',error);
-        res.status(500).json({message:'Internal server error'});
-    }
-})
-
-app.post('/products',async (req,res)=>{
-    try{
-        const {name,price,quantity} = req.body;
-        const newProduct = new Product({name,price,quantity});
-        await newProduct.save();
-        res.status(201).json({message:'Product added successfully'});
-    }catch(error){
-        console.error('Error adding product:',error);
-        res.status(500).json({message:'Internal server error'});
-    }
-})
-
-app.put('/products/:id',async (req,res)=>{
-    try{
-        const {name,price,quantity} = req.body;
-        await Product.findByIdAndUpdate(req.params.id,{name,price,quantity});
-        res.status(200).json({message:'Product updated successfully'});
-    }catch(error){
-        console.error('Error updating product:',error);
-        res.status(500).json({message:'Internal server error'});
-    }
-})
-
-app.delete('/products/:id',async (req,res)=>{
-    try{
-        await Product.findByIdAndDelete(req.params.id);
-        res.status(200).json({message:'Product deleted successfully'});
-    }catch(error){
-        console.error('Error deleting product:',error);
-        res.status(500).json({message:'Internal server error'});
-    }
-})
-// Start the server
-app.listen(3000, () => {
-    console.log('Server started on port 3000');
-});
+import React, { useState } from "react";
+import "./App.css";
+
+function App() {
+  const [expenses, setExpenses] = useState([]);
+  const [description, setDescription] = useState("");
+  const [amount, setAmount] = useState("");
+  const [category, setCategory] = useState("");
+  const [editId, setEditId] = useState(null);
+
+  // Add new expense
+  const addExpense = () => {
+    if (editId !== null) {
+      const updatedExpenses = expenses.map((expense) =>
+        expense.id === editId
+          ? { ...expense, description, amount, category }
+          : expense
+      );
+      setExpenses(updatedExpenses);
+      setEditId(null);
+    } else {
+      const newExpense = {
+        id: Date.now(),
+        description,
+        amount: parseFloat(amount),
+        category,
+      };
+      setExpenses([...expenses, newExpense]);
+    }
+    resetFields();
+  };
+
+  // Delete expense
+  const deleteExpense = (id) => {
+    setExpenses(expenses.filter((expense) => expense.id !== id));
+  };
+
+  // Edit expense
+  const editExpense = (id) => {
+    const expense = expenses.find((expense) => expense.id === id);
+    setDescription(expense.description);
+    setAmount(expense.amount);
+    setCategory(expense.category);
+    setEditId(id);
+  };
+
+  // Reset input fields
+  const resetFields = () => {
+    setDescription("");
+    setAmount("");
+    setCategory("");
+  };
+
+  // Calculate total expenses
+  const totalExpenses = expenses.reduce((acc, expense) => acc + expense.amount, 0);
+
+  return (
+    <div className="App">
+      <h1>Expense Tracker</h1>
+
+      <div className="form">
+        <input
+          type="text"
+          placeholder="Description"
+          value={description}
+          onChange={(e) => setDescription(e.target.value)}
+        />
+        <input
+          type="number"
+          placeholder="Amount"
+          value={amount}
+          onChange={(e) => setAmount(e.target.value)}
+        />
+        <input
+          type="text"
+          placeholder="Category"
+          value={category}
+          onChange={(e) => setCategory(e.target.value)}
+        />
+        <button onClick={addExpense}>
+          {editId !== null ? "Update Expense" : "Add Expense"}
+        </button>
+      </div>
+
+      <div className="expense-list">
+        <h2>Your Expenses</h2>
+        {expenses.length === 0 ? (
+          <p>No expenses added yet</p>
+        ) : (
+          <ul>
+            {expenses.map((expense) => (
+              <li key={expense.id}>
+                <strong>{expense.description}</strong> - ${expense.amount} -{" "}
+                {expense.category}
+                <button onClick={() => editExpense(expense.id)}>Edit</button>
+                <button onClick={() => deleteExpense(expense.id)}>Delete</button>
+              </li>
+            ))}
+          </ul>
+        )}
+      </div>
+
+      <div className="summary">
+        <h2>Total Expenses: ${totalExpenses.toFixed(2)}</h2>
+      </div>
+    </div>
+  );
+}
+
+export default App;