In this article, we will be exploring a common and simple problem in computer programming: finding the largest number among three given numbers. The language we will use to address this problem is C, a general-purpose, procedural computer programming language. C provides the constructs necessary to map efficiently to typical machine instructions. In other words, it is a popular language for system programming, though it is also used for a variety of other applications.
Basics of the C Programming Language
Before diving into the problem, let’s start with a brief introduction to the C programming language. Developed in the early 1970s, C has influenced many other languages, such as C++, C#, Java, and even Python to some extent. The language is known for its flexibility, efficiency, and control, and is commonly used in system programming, game development, and embedded systems.
C programming is characterized by its use of functions, variables, loops, decision making statements (if-else), and more. All these components are fundamental to building a C program and will be used in the problem we’ll be discussing.
C Program Solution
Let’s now delve into the actual C program. We’ll discuss the code piece by piece, and then present the whole program.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | #include <stdio.h> int main() { double num1, num2, num3; printf("Enter three numbers: "); scanf("%lf %lf %lf", &num1, &num2, &num3); if (num1 >= num2 && num1 >= num3) printf("%.2lf is the largest number.", num1); else if (num2 >= num1 && num2 >= num3) printf("%.2lf is the largest number.", num2); else printf("%.2lf is the largest number.", num3); return 0; } |
Now, let’s analyze this program:
Header Files: The #include is a preprocessor command which includes the standard input-output library in the program. This library allows the use of input/output functions.
Main Function: The int main() is the main function where the execution of any C program begins.
Variable Declaration: double num1, num2, num3; declares three variables of the type double. These will store the three numbers that we will be comparing.
Taking Inputs: printf(“Enter three numbers: “); displays a message to the user. Then, scanf(“%lf %lf %lf”, &num1, &num2, &num3); reads three inputs from the user and stores them in num1, num2, and num3.
Condition Checking: We use if and else if statements to compare the three numbers. The conditions num1 >= num2 && num1 >= num3 and num2 >= num1 && num2 >= num3 check if num1 or num2 are larger than or equal to the other two numbers. If neither of these conditions is true, then num3 must be the largest, which is why we can use an else statement for it.
Output: The printf(“%.2lf is the largest number.”, num1/num2/num3); statement is used to print the largest number. The placeholder %.2lf is used to print a double type number with two places of decimal.
Return Statement: Finally, return 0; is used to signify that the program has executed successfully. It is not mandatory but is considered good practice to use it at the end of the main() function.
And that’s it! This simple C program demonstrates a basic use of input/output, variable usage, and control flow constructs in the C language, while solving the problem of finding the largest among three numbers.