Logical Operators

C Categories

Description

C language allows two types of logical operators - logical AND (&&) and logical OR (||) . These logical operators allows you to logically combine boolean (true/false) values of two or more regular expressions.

Eg. Selecting a female client, who knows programming or networking.

By using two variables client and knows, the condition statement for this problem becomes as
if ( client != 'male' && knows == 'programming' || knows == 'networking' )

Source code

/* A client who knows programming or networking with gender female*/
#include <stdio.h>
#include <conio.h>
void main()
{
int x,y,z;
char knows,gender;
clrscr();
printf("Enter gender (M or F) : ");
scanf("%c",&gender);
while(1)
{
printf("Enter option you know \n 1)Programming\n 2)Hardware\n 3)C \n");
scanf("%d",&x);
switch(x)
{
case 1:
knows='P';
break;
case 2:
knows='H';
break;
case 3:
knows='N';
break;
default:
printf("Wrong option selected, please try again");
continue;
};
break;
}
if (knows=='P' || knows=='N' && gender!='M')
{
printf("You are selected");
}
else
{
printf("Sorry!, You are rejected.");
}
getch();
}

Program working steps

First 5 lines of the program are basic about comment, preprocessor directive statements and void main function.
6th and 7th line is the declaration of integer and character variables and then clearing of the screen using clrscr() function.
Printf statement prints the double quoted text and scanf stores the character value in variable gender.
While(1) statement is used here to repeat switch case loop, if the user enters invalid input using continue statement.
Program prompts the user to enter the option you know 1,2 or 3 for programming hardware and networking.
Switch case loop traverses the cases till the match is found, if not then default case will be implemented.
Case implementation stops when it reaches break or continue statement in this program.
After the break of switch case loop, while(1) loop also terminates as it is followed by break statement.
If condition expression on line no.33 is true it will print 'You are selected' else 'Sorry, you are rejected'.
Getch() function to avoid closing of program immediately as it takes input from the user and doesn't prints on the screen.

« Previous Point - Assignment Operators

Next Point - Bitwise Operators »

Tip Box

Operator precedence