If and else statement

If and else statement:

                                    In c++ the compiler run our program instruction by instruction or line by line.Sometime we have some specific statement or instruction that we want to run when certain condition full fill. For this c++ provide the conditional statement.  If statement use for this purpose .

Syntax

If(condition)

Statement ;

If is a keyword that take a condition if the condition is true then the statement will be run otherwise the statement will not be run.

Example:

If(x==100)

Cout<<”congrats your condition is true”;

You can use more than one statement that is effect by if condition for this we use {}. Every statement that will be written within {} will be run when if condition is true

Syntax

If(condition)

{

Statement 1;

Statement 2;

.

.

.

Statement n;

}

Example:

If(x==100)

{

Cont<<”the value of x is 100”;

Cout<<”congratulaion your output is diaplaying”;

Cout<<”this example is written by programminglogic.net”;

}

If condition will be false than nothing will be happened no output will be display.  so if we want that when  conditon will false some instruction should be run then we use if else

Syntax of if ,else statement

If(condition)

Statement;

else

Statement;

Syntax for more than one statement

If(condition)

{

Statement 1;

Statement 2;

.

.

Statement n;

}

else

{

Statement 1;

Statement 2;

.

.

Statement n;

}

Example:

If(x==100)

Cout<<”the value of x is 100”;

else

Cont<<”the value of x is less than or greater than 100”;

Flow chart of if ,else statement:

if else 

Nested if ,else:

                          We use if ,else  statement for conditional statement when we have multiple condition which is related to each other then we use nested if ,else . we can simply say that a nested if ,else statement is an if ,else statement with  another  if else statement inside it . we use it when we have more than one choice  . 

Syntax of nested if,else statement:

If(condition)

//Some code

elseif(condition)

//some code

Elseif(condition)

//some code

.

.

.

.

.else

//Some code

The  nested  if else  statement means that if the top condition is not true, then try checking other condition. If anyone condition is true , then ignore the rest of the available conditions. If no one condition is true then execute the else part of the statement .

flow chart:

nested if else