Elements of programming-4

If statement.

It is a conditional statement. It conditionally executing a branch of statements .There are different types of if statement.

1.       simple if

2.       if-else

3.       if-else if-else

4.       switch statement.

Simple If statement:

A relational expression is checked. If the condition is true a block of coding will be executed.if  it returns false the block of coding will not get executed.

For example take the following c program

.

#include<stdio.h>

#include<conio.h>

void main()

{
int mark;

Clrscr();

printf(“enter your score”);

scanf(“%d”,&mark);

printf(“your score is %d”,mark);

if(mark>=90)

{

printf(“excellent”);

}

getch();

}

Program explanation:

The above program asks the score as input. It prints your  mark.if your mark>=90 then it additionally prints the output excellent.

If—else

In this case a relational expression is tested .if the result is true then a block of coding will be executed.if it returns false another block of coding will be executed.

#include<stdio.h>

#include<conio.h>

void main()

{
int mark;

Clrscr();

printf(“enter your score”);

scanf(“%d”,&mark);

printf(“your score is %d”,mark);

if(mark>=40)

{

printf(“pass”);

}

Else

{

Printf(“fail”);

}

getch();

}

Program explanation:

In the above c program mark is input. If it is greater than or equal  to 40 result is printed as false.

If the mark<40 else part will be executed  and printed as fail

                                                --------to be continued

                                                                muthu karthikeyan madurai