C – Nested If Block

Nested If: Defining if block inside another if block.

Syntax:

if(condition){
	if(condition){
		if-if-Stat;
	}
	else{
		if-else-stat;
	}
}
else{
	if(condition){
		else-if-stat;
	}
	else{
		else-else-stat;
	}
}

Flow Chart:

Check the number is Even or not only if the number is positive:

#include<stdio.h> int main() {             int n;             printf(“Enter number : “);             scanf(“%d”, &n);             if(n>0)             {                         if(n%2==0)                                     printf(“Even number\n”);                         else                                     printf(“Not even number\n”);              }             else                         printf(“Not a positive number\n”);                               return 0; }

Check biggest of 2 numbers only if the numbers are equal:

#include<stdio.h> int main() {             int a, b;             printf(“Enter 2 numbers : “);             scanf(“%d%d”, &a, &b);             if(a!=b)             {                         if(a>b)                                     printf(“a is big\n”);                         else                                     printf(“b is big\n”);                   }             else                         printf(“Both are equal numbers\n”);                             return 0; }

Print student grade only if the student passed in all subjects:

• Minimum pass marks must be >=35
• Display the Grade only if the student passed in all subjects.
• If the average >= 60 then print “A-Grade”
• If the average >= 50 then print “B-Grade”
• If the average >= 40 then print “C-Grade”

#include<stdio.h> int main(){             int m1, m2, m3;             printf(“Enter 3 marks : “);             scanf(“%d%d%d”, &m1, &m2, &m3);             if(m1>=35 && m2>=35 && m3>=35)             {                         int avg = (m1+m2+m3)/3;                         if(avg>=60)                                     printf(“Grade-A\n”);                         else if(avg>=50)                                     printf(“Grade-B\n”);                         else                                     printf(“Grade-C\n”);                 }             else                         printf(“Student failed\n”);                                return 0; }

Read month number and display days:

• If the month is invalid (not from 1 to 12) then display “Invalid month”
• Month-2 has 28 or 29 days
• Months-4,6,9,11 has 30 days
• Remaining months has 31 days

#include<stdio.h> int main() {             int month;             printf(“Enter month : “);             scanf(“%d”, &month);             if(month>=1 && month<=12)             {                         if(month==2)                                     printf(“28 days \n”);                                         else if(month==4 || month==6 || month==9 || month==11)                                     printf(“30 days \n”);                             else                                     printf(“31 days \n”);                 }             else                         printf(“Invalid month given \n”);                      return 0; }