Conditional statements of c language

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Conditional Statements
When ever you want to perform a set of operations based on a condition(s) If / If-Else / Nested ifs are used.

You can also use if-else , nested IFs and IF-ELSE-IF ladder when multiple conditions are to be performed on a single variable.

If
Syntax
if(conditional-expression)
{
//code
}
Example
#include <stdio.h>
int main()
{
int x = 30;
int y = 30;
```
 if ( x == y) {
   printf("x and y are equal");
 }
```

}
Check result here
2. If-else
Syntax
if(conditional-expression)
{
//code
} else {
//code
}
Example
#include <stdio.h>
int main()
{
int x = 30;
int y = 20;

if ( x == y) {
printf("x and y are equal");
} else {
printf("x and y are not equal");
}
}
Check result here
3. If-else-if ladder
Syntax
if(conditional-expression-1)
{
//code
} else if(conditional-expression-2) {
//code
} else if(conditional-expression-3) {
//code
}
....
else {
//code
}
Example
#include <stdio.h>
int main()
{
int age = 15;

if ( age <= 1 && age >= 0) {
  printf("Infant");
} else if (age > 1 && age <= 3) {
    printf("Toddler");
} else if (age > 3 && age <= 9) {
    printf("Child");
} else if (age > 9 && age <= 18) {
    printf("Teen");
} else if (age > 18) {
    printf("Adult");
} else {
    printf("Invalid Age");
}

}
Check result here
4. Nested-If
Nested-Ifs represents if block within another if block.

Syntax
if(conditional-expression-1) {
//code
if(conditional-expression-2) {
//code
if(conditional-expression-3) {
//code
}
}
}
Example
#include <stdio.h>
int main()
{
int age = 50;
char resident = 'Y';
if (age > 18)
{
if(resident == 'Y'){
printf("Eligible to Vote");
}
}
}
Check result here
Switch
Switch is an alternative to IF-ELSE-IF ladder and to select one among many blocks of code.

Syntax
switch(conditional-expression){
case value1:
//code
break; //optional
case value2:
//code
break; //optional
...

default:
//code to be executed when all the above cases are not matched;
}
Example
#include <stdio.h>
int main()
{
int day = 3;

  switch(day){
    case 1: printf("Sunday");
    break;
    case 2: printf("Monday");
    break;
    case 3: printf("Tuesday");
    break;
    case 4: printf("Wednesday");
    break;
    case 5: printf("Thursday");
    break;
    case 6: printf("Friday");
    break;
    case 7: printf("Saturday");
    break;
    default:printf("Invalid day");
    break; 
  }

}
Check Result here