Two-dimensional arrays in C - Mini Project: Build & Apply

Working with Two-Dimensional Arrays in C

📖 Scenario: You are helping a small shop owner keep track of daily sales for different products over a week. The sales data is stored in a table where each row represents a product and each column represents a day of the week.

🎯 Goal: Create a program that stores sales data in a two-dimensional array, calculates the total sales for each product, and then prints the totals.

📋 What You'll Learn

Create a two-dimensional array called sales with 3 rows and 7 columns to store sales numbers.

Create an integer variable called total to hold the sum of sales for each product.

Use a for loop with variable i to go through each product (row).

Use a nested for loop with variable j to go through each day (column) for the current product.

Calculate the total sales for each product by adding the daily sales.

Print the total sales for each product using printf.

💡 Why This Matters

🌍 Real World

Two-dimensional arrays are useful for storing tables of data like sales, schedules, or pixel colors in images.

💼 Career

Understanding how to work with two-dimensional arrays is important for jobs involving data analysis, software development, and any task that requires managing grid-like data.

1

Create the sales data array

Create a two-dimensional integer array called sales with 3 rows and 7 columns. Initialize it with these exact values: first row {10, 12, 11, 14, 13, 15, 16}, second row {8, 9, 7, 10, 11, 12, 13}, third row {5, 6, 5, 7, 8, 6, 7}.

C

# Create the sales array with the exact values
# Your code here

Need a hint?

Use curly braces to group each row's values inside the array initialization.

2

Create a variable for total sales

Create an integer variable called total and set it to 0. This will hold the sum of sales for each product.

C

int sales[3][7] = {
    {10, 12, 11, 14, 13, 15, 16},
    {8, 9, 7, 10, 11, 12, 13},
    {5, 6, 5, 7, 8, 6, 7}
};

// Create the total variable and set it to 0
// Your code here

Need a hint?

Remember to specify the type int and initialize total to zero.

3

Calculate total sales for each product

Use a for loop with variable i from 0 to 2 to go through each product (row). Inside it, set total to 0. Then use a nested for loop with variable j from 0 to 6 to go through each day (column). Add sales[i][j] to total inside the inner loop.

C

int sales[3][7] = {
    {10, 12, 11, 14, 13, 15, 16},
    {8, 9, 7, 10, 11, 12, 13},
    {5, 6, 5, 7, 8, 6, 7}
};

int total = 0;

// Use for loops to calculate total sales for each product
// Your code here

Need a hint?

Reset total to zero for each product before adding daily sales.

4

Print total sales for each product

Inside the outer for loop, after the inner loop, use printf to print the total sales for product i. Use this exact format: Product %d total sales: %d\n, where the first %d is i + 1 and the second %d is total.

C

int sales[3][7] = {
    {10, 12, 11, 14, 13, 15, 16},
    {8, 9, 7, 10, 11, 12, 13},
    {5, 6, 5, 7, 8, 6, 7}
};

int total = 0;

for (int i = 0; i < 3; i++) {
    total = 0;
    for (int j = 0; j < 7; j++) {
        total += sales[i][j];
    }
    // Print the total sales for product i
    // Your code here
}

Need a hint?

Use printf("Product %d total sales: %d\n", i + 1, total); to print the results.