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If-Else

In C programming, the if-else statement is a fundamental control structure that allows you to execute different blocks of code based on the evaluation of a condition.

Syntax of if-else :

if (condition) { // Code to execute if condition is true } else { // Code to execute if condition is false }

How it works :

Condition : The condition is an expression that evaluates to either true (non-zero) or false (zero).
If Block : If the condition evaluates to true, the code inside the if block is executed.
Else Block : If the condition evaluates to false, the code inside the else block is executed.

Example :

C Code

													
                                                      
#include <stdio.h>
main() {
    int n;
    printf("Enter an integer: ");
    scanf("%d", &n);
    if (n > 0) {
        printf("The number is positive");
    } else {
        printf("The number is negative.");
    }  
}
                                                       

													
												

Output :
Enter an integer: 5
The number is positive
Enter an integer: -5
The number is negative.

Explanation :
n > 0
If the condition is true, the first block of code is executed.
If the condition is false, the else block of code is executed.

Nested if-else :

Nested if else statements are used to perform different actions based on multiple conditions.

Example of nested if-else :

C Code

													
                                                      
#include <stdio.h>
main() {
    int number;
    printf("Enter a number: ");
    scanf("%d", &number);
    if (number > 0) {
        printf("The number is positive.");
    } else if (number == 0) {
        printf("The number is zero.");
    } else {
        printf("The number is negative.");
    }
}
                                                       

													
												

Output :
Enter a number: 5
The number is positive.
Enter a number: 0
The number is zero.
Enter a number: -7
The number is negative.

Problems & Solutions :

C Code

													# Write a program to find largest of two numbers.
                                                      
#include<stdio.h>
main()
{
	int a,b;
	printf("Enter the two no : ");
	scanf("%d%d",&a,&b);
	if(a>b)
	printf("Largest=%d",a);
	else
	printf("Largest=%d",b);	
}
                                                       

													
												

Output :
Enter the two no : 5
7
Largest=7

C Code

													# Write a program to accept a number and check whether the number is Automorphic number or not. An automorphic number is a number which is present in the last digit(s) of its square
                                                      
#include<stdio.h>
main()
{
	int n;
	printf("Enter the value:");
	scanf("%d",&n);
	if(n*n%10==n || n*n%100==n || n*n%1000==n)
	printf("Automorphic no",n);
	else
	printf("Not=%d",n);
	
}
                                                       

													
												

Output :
Enter the value:25
Automorphic no

C Code

													# Write a program to accept a Character and check whether it is a Vowel or Consonant
                                                      
#include <stdio.h>
main() {
    char c;
    printf("Enter a character: ");
    scanf("%c", &c);
    if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' ||
        c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U') {
        printf("%c is a vowel.", c);
    } else {
        printf("%c is a consonant.", c);
    }
}
                                                       

													
												

Output :
Enter a character: s
s is a consonant.
Enter a character: a
a is a vowel.

Importance of if-else :

Flexibility : The if-else statement provides the flexibility to handle various scenarios within a program.
Decision Making : It is essential for decision-making processes, allowing programs to respond to different conditions and inputs.
Readability and Maintainability : Proper use of if-else statements can enhance the readability and maintainability of the code, making it easier to understand and modify.

Conclusion :

Understanding and using if-else statements effectively allows you to create more complex and responsive programs by making decisions based on different conditions.

If-Else

Syntax of if-else :

How it works :

Example :

Nested if-else :

Example of nested if-else :

Problems & Solutions :

Importance of if-else :

Conclusion :

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