Exercise 3: Formatted Printing

Keep that Makefile around since it'll help you spot errors, and we'll be adding to it when we need to automate more things.

Many programming languages use the C way of formatting output, so let's try it:

View Source file ex3.c Only

#include <stdio.h>

int main()
{
    int age = 10;
    int height = 72;

    printf("I am %d years old.\n", age);
    printf("I am %d inches tall.\n", height);

    return 0;
}

Once you've finished that, do the usual make ex3 to build and run it. Make sure you fix all warnings.

This exercise has a whole lot going on in a small amount of code, so let's break it down:

• First we're including another header file called stdio.h. This tells the compiler that you're going to use the standard Input/Output functions. One of those is printf.

• Then we're using a variable named age and setting it to 10.

• Next we're using a variable height and setting it to 72.

• Then we're adding the printf function to print the age and height of the tallest 10-year-old on the planet.

• In printf, you'll notice we're including a format string, as seen in many other languages.

• After this format string, we're putting in the variables that should be "replaced" into the format string by printf.

The result is giving printf some variables and it's constructing a new string and then printing it to the terminal.