Section 6.1 Arrays: An Easy Example#
Adapted from: “Beej’s Guide to C Programming” by Brian (Beej Jorgensen) Hall: Beej’s Guide to C Programming: 6.1 An Easy Example
Brian (Beej Jorgensen) Hall Website
Program for Creating, Initializing, and Printing an Array#
#include <stdio.h>
int main(void)
{
int i;
float f[4]; // Declare an array of 4 floats
f[0] = 3.14159; // Indexing starts at 0, of course.
f[1] = 1.41421;
f[2] = 1.61803;
f[3] = 2.71828;
// Print them all out:
for (i = 0; i < 4; i++) {
printf("%f\n", f[i]);
}
}
Explanation of the Above Code#
Include the Standard I/O Library: The program starts by including the standard input/output library with
#include <stdio.h>
, which allows us to use functions likeprintf()
.Main Function: The
main()
function is the entry point of the program.Variable Declaration: Inside the
main()
function, we declare an integer variablei
and a float arrayf
with 4 elements.Array Initialization: We assign values to each element of the array
f
using indexing. The first element isf[0]
, the second isf[1]
, and so on.Loop to Print Values: We use a
for
loop to iterate through the array and print each value usingprintf()
. The loop runs from0
to3
, which corresponds to the indices of the array.Output: The program prints the values of the array
f
to the console, each on a new line.
Output of the Program#
When you run the program, it will output the following values:
3.141590
1.414210
1.618030
2.718280
Summary#
This simple program demonstrates how to create, initialize, and print an array in C. It uses a for
loop to iterate through the array and print each value, showcasing the basic syntax and functionality of arrays in C programming.
Compile and Run Code#
Use Python to Change to Working Directory#
import os
root_dir = os.getcwd()
code_dir = root_dir + "/" + "C_Code"
os.chdir(code_dir)
build_command = os.system("gcc -o section_6_1_easy_example section_6_1_easy_example.c")
exec_status = os.system("./section_6_1_easy_example")
3.141590
1.414210
1.618030
2.718280