Logical operators

These operators provide logic to our programming , there are basically  3 types of logical operator

And operator	&&
Or operator	||
Not operator	!

We use logical operators with other operators in order to make our programming more efficient

Now to better understand this let us make a program that’s  takes a number called marks as input and display the result based on following conditions

0 to 30 ---------- D

31  to 40 ------- C

41 to 50 --------B

51 to 70 --------A

71 to 100 ------ A+

So our program will look like

main()

{

      int marks;

     

      printf("Pl enter your marks\n");

      scanf("%d",&marks);

     

             if((marks >=71) && (marks <=100))           

              {

               printf("A+");

              }

              

              else  if((marks >=51)&&(marks <=70))

              {

               printf("A");

              }

              

              else if((marks >=41)&&(marks <=50))

              {

                printf("B");

              }

              

               else if((marks >=31)&&(marks <=40))

              {

               printf("C");

              }

             

              else  if((marks >= 0)&&(marks <=30))

              {

               printf("D");

              }

              

              else

              {

               printf("invalid");

              }

                

               getch();

              

              }

We can have combinations of  "and , or , not" to have many results

Or and “and” have same syntax with different symbols but not is slightly different , for example if we have to check if a value is not some value then we write

if(!(variable == value));