Branching

C language executes program statements in a sequence. Sometimes we need to alter the flow of sequence of statements. This is possible using Branching statements offered by C language. They are also known as control statements. Programmer can jump from one part of the program to other with the help of such statements. 

Branching Statements in C:

• if statement: Executes a block of code if a condition is true.
• else statement: Executes a block of code if the condition in the if statement is false.
• switch statement: Selects one of multiple blocks of code to execute based on the value of an expression.

Key Concepts to learn:

• Boolean expressions: Evaluate to either true (non-zero) or false (zero).
• Control flow: The order in which statements are executed.
• Nested statements: Placing one statement inside another.

Followings are broad categories of C language Branching Statements:

1. if statement

2. if…else statement

3. nested if statement

4. switch statement

Let’s learn branching statement by executing following programs.

Programs based on if statement Check: Given number is positive or not using if statement. C Program to find bigger number. C Program to find largest number from given three numbers. C program to display Good morning message based on given time.

Programs based on if…else statement Check: Given number is positive or not using if..else statement. C Program to check whether entered number is odd or even. C Program to check given string is Palindrome or not using if...else statement. C program to check whether a given character is an alphabet, digit or special character.

Programs based on nested if statement Example of nested if statement. Check: A is greater than B and C.

Programs based on switch statement C Program to convert given number (between 1 to 5) into words using switch.

Sample Programs

Program to check whether entered number is odd or even.

#include<stdio.h>
int main()
{
 int number;

 printf("Enter number:");
 scanf("%d",&number);

 if(number%2 == 0)
  printf("Entered number is even.");
 else
  printf("Entered number is odd.");
 return 0;
}
/* Sample Output
Enter number:5
Entered number is odd.
*/

C Program to convert given number (between 1 to 5) into words using switch.

#include<stdio.h> void main () {  int number;  printf("Enter your number:");  scanf("%d",&number);  switch(number)  {   case 1 :printf("One");              break;   case 2 :printf("Two");              break;   case 3 :printf("Three");              break;   case 4 :printf("Four");              break;   case 5 :printf("Five");              break;   default :printf("Invalid number\n" );  } } /*Output Enter your number:5 Five */

Check:Given number is positive or not using if..else statement.

#include<stdio.h> void main() {   int number;   printf("Enter number:");   scanf("%d",&number);   if(number > 0)       printf("Number is positive.");   else       printf("Number is not positive."); } /*Output Enter number:11 Number is positive. */