Learn to Program with C_ Learn to Program using the Popular C Programming Language ( PDFDrive )

Chapter 1 ■ Elementary Programming Concepts
Program P1.4 shows how we can write this algorithm as a C program.
Program P1.4
//This program prints the sum of 14 and 25. It shows how
//to declare variables in C and assign values to them.
#include <stdio.h>
int main() {
int a, b, sum;
a = 14;
b = 25;
sum = a + b;
printf("%d + %d = %d\n", a, b, sum);
}
When run, this program will print the following:
14 + 25 = 39
In C, variables are declared as integer using the required word int. (In programming
terminology, we say that int is a reserved word.) Thus, the statement
int a, b, sum;
declares that a, b, and sum are integer variables. In C, all variables must be declared before they are
used in a program. Note that the variables are separated by commas, with a semicolon after the
last one. If we need to declare just one variable (a, say), we will write
int a;
a = 14;
The statement
is C’s way of writing the assignment statement
set a to 14
It is sometimes pronounced “a becomes 14.” In C, an assignment statement consists of a
variable (a in the example), followed by an equals sign (=), followed by the value to be assigned to
the variable (14 in the example), followed by a semicolon. In general, the value can be a constant
(like 14), a variable (like b), or an expression (like a + b). Thus,
set b to 25
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