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

#define MAX_EXPENSES 100

struct Expense {
    char name[50];
    float amount;
};

int main() {
    float monthly_income;
    int num_expenses = 0;
    struct Expense expenses[MAX_EXPENSES];
    float total_expenses = 0;

    // Sequential Structure: Gather user input
    printf("Enter your monthly income: ");
    scanf("%f", &monthly_income);

    printf("Enter the number of expenses: ");
    scanf("%d", &num_expenses);

    // Gather expense details
    for (int i = 0; i < num_expenses; i++) {
        printf("Enter name of expense #%d: ", i + 1);
        scanf("%s", expenses[i].name);

        printf("Enter amount for expense #%d: ", i + 1);
        scanf("%f", &expenses[i].amount);

        total_expenses += expenses[i].amount;
    }

    // Decision/Selection Structure: Check if expenses exceed income
    if (total_expenses > monthly_income) {
        printf("WARNING: Your expenses exceed your monthly income!\n");
        printf("Consider reducing your expenses.\n");
    } else {
        printf("Your expenses are within your monthly income.\n");
    }

    // Iteration/Loop Structure: Display menu
    int choice;
    while (1) {
        printf("\nMenu:\n");
        printf("1. View summary of expenses\n");
        printf("2. Add a new expense\n");
        printf("3. Delete an existing expense\n");
        printf("4. Exit\n");

        printf("Enter your choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                printf("\nSummary of Expenses:\n");
                for (int i = 0; i < num_expenses; i++) {
                    printf("%s: %.2f\n", expenses[i].name, expenses[i].amount);
                }
                printf("Total Expenses: %.2f\n", total_expenses);
                break;
            case 2:
                if (num_expenses < MAX_EXPENSES) {
                    printf("Enter name of new expense: ");
                    scanf("%s", expenses[num_expenses].name);

                    printf("Enter amount for new expense: ");
                    scanf("%f", &expenses[num_expenses].amount);

                    total_expenses += expenses[num_expenses].amount;
                    num_expenses++;
                } else {
                    printf("Cannot add more expenses. Reached maximum limit.\n");
                }
                break;
            case 3:
                if (num_expenses > 0) {
                    printf("Enter index of expense to delete (1 to %d): ", num_expenses);
                    int index;
                    scanf("%d", &index);
                    index--;

                    if (index >= 0 && index < num_expenses) {
                        total_expenses -= expenses[index].amount;

                        for (int i = index; i < num_expenses - 1; i++) {
                            strcpy(expenses[i].name, expenses[i + 1].name);
                            expenses[i].amount = expenses[i + 1].amount;
                        }

                        num_expenses--;
                    } else {
                        printf("Invalid index.\n");
                    }
                } else {
                    printf("No expenses to delete.\n");
                }
                break;
            case 4:
                printf("Exiting program.\n");
                exit(0);
            default:
                printf("Invalid choice. Please try again.\n");
        }
    }

    return 0;
}