C105: Condition

A conditional statement is a statement that has a condition. the condition returns true or false when evaluated. That means it is comparison statement or a logical statement. For example a > 6 where it returns true if value of a more than 6 otherwise it returns false.
Example for logical statement is TRUE && TRUE is TRUE

Comparison

Symbol Means
> more than
if first operand is more than the second operand, it will return true. Otherwise it will return false
5 > 1 is TRUE
5 > 6 is FALSE
< less than
if first operand is less than the second operand it will return true. Or else it will return false.
3 < 5 is TRUE
5 <  1 is FALSE
>=more than or equal
if first operand is more than or equal to second operand, it will return true. Otherwise it will return false
4>=2 TRUE
4>= 6 FALSE
5 > 5 is FALSE but 5 >= 5 is TRUE
<=less than or equal
if first operand is less than or equal to second operand, it will return true. Otherwise it will return false
4<=2 FALSE
4<= 6 TRUE
5 < 5 is FALSE but 5 <= 5 is TRUE
==equal
if both the operands are equal it returns true, Otherwise it returns false.
3 == 3 is TRUE
2 == 3 is FALSE
!=not equal
if both the operands are not equal it returns true, Otherwise it returns false.
3 != 4 is TRUE
2 != 2 is FALSE

Logical

SymbolMeans
&&AND
 if both operands are TRUE it returns TRUE. Otherwise it returns FALSE
(5 > 2) && (10 > 6) is TRUE
(5 < 2) && (10 > 6) is FALSE
(5 > 2) && (10 < 6) is FALSE
(5 < 2) && (10 < 6) is FALSE
||OR 
if both operands are FALSE it returns FALSE. Otherwise it returns TRUE
(5 > 2) && (10 > 6) is TRUE
(5 < 2) && (10 > 6) is TRUE
(5 > 2) && (10 < 6) is TRUE
(5 < 2) && (10 < 6) is FALSE
!NOT 
if the operand is FALSE it returns TRUE, and if the operand is TRUE it returns FALSE.
!(5>2) is FALSE
!(5<2) is TRUE

Selection statement

if statement

if statement evaluates the condition to determine whether to execute the code block or not to. following is a syntax for the if condition.

if(condition){
  //code block
}

example

if(6 > 3){
  printf("6 is more than 3");
}

this example will display the message because the condition 6 > 3 is TRUE.

if(6 < 3){  
  printf("6 is more than 3");
}

The second code will not display the message because the condition is FALSE, so the code block is not entered.

More on conditional statement will be discussed in part 2.

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