#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// Structure to represent an expense entry
struct Expense {
    char category[50];
    float amount;
};

// Function to add an expense entry
void addExpense(struct Expense *expenses, int *count) {
    printf("Enter expense category: ");
    scanf("%s", expenses[*count].category);

    printf("Enter expense amount: ");
    scanf("%f", &expenses[*count].amount);

    (*count)++;
}

// Function to display all expenses
void displayExpenses(struct Expense *expenses, int count) {
    printf("\nExpense Report:\n");
    for (int i = 0; i < count; ++i) {
        printf("%s: $%.2f\n", expenses[i].category, expenses[i].amount);
    }
}

// Function to calculate and display total expenses
void displayTotalExpense(struct Expense *expenses, int count) {
    float total = 0;
    for (int i = 0; i < count; ++i) {
        total += expenses[i].amount;
    }
    printf("\nTotal Expense: $%.2f\n", total);
}

// Function to save expenses to a file
void saveExpenses(struct Expense *expenses, int count) {
    FILE *file = fopen("expenses.txt", "w");
    if (file == NULL) {
        printf("Error opening file for writing.\n");
        return;
    }

    for (int i = 0; i < count; ++i) {
        fprintf(file, "%s %.2f\n", expenses[i].category, expenses[i].amount);
    }

    fclose(file);
}

// Function to load expenses from a file
int loadExpenses(struct Expense *expenses) {
    FILE *file = fopen("expenses.txt", "r");
    if (file == NULL) {
        printf("No expenses found.\n");
        return 0;
    }

    int count = 0;
    while (fscanf(file, "%s %f", expenses[count].category, &expenses[count].amount) != EOF) {
        count++;
    }

    fclose(file);
    return count;
}

int main() {
    struct Expense expenses[100]; // Assuming a maximum of 100 expenses
    int count = 0;

    // Load existing expenses from file
    count = loadExpenses(expenses);

    int choice;
    do {
        printf("\nExpense Tracker Menu:\n");
        printf("1. Add Expense\n");
        printf("2. View Expenses\n");
        printf("3. View Total Expense\n");
        printf("4. Save and Exit\n");
        printf("Enter your choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                addExpense(expenses, &count);
                break;
            case 2:
                displayExpenses(expenses, count);
                break;
            case 3:
                displayTotalExpense(expenses, count);
                break;
            case 4:
                saveExpenses(expenses, count);
                printf("Expenses saved. Exiting...\n");
                break;
            default:
                printf("Invalid choice. Try again.\n");
        }
    } while (choice != 4);

    return 0;
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}