31 C Programming Exercises and Solutions | Pythonista Planet (2024)

If you know the fundamentals of C programming, now you can focus on solving some coding questions to practice. You will be able to understand all the basic concepts of C programming if you solve some coding problems.

In this post, I have put together some C programming problems that you can use for practice. I have also provided the C code solutions and the corresponding output for your reference.

Try to solve these coding challenges by yourself and get better at C programming language. Let’s dive right in.

1. C program to check whether the given number is even or odd

#include <stdio.h>int main() { int myNumber; printf("Enter a number: "); scanf("%d",&myNumber); int x = myNumber%2; if(x==0){ printf("The number is Even. \n"); }else{ printf("The number is Odd. \n"); } return 0;}

Output:

2. C program to convert the temperature in Degree Centigrade to Fahrenheit

#include <stdio.h>int main() { int c; printf("Enter temperature in Centigrade: "); scanf("%d",&c); float f = ((9*c)/5)+32; printf("Temperature in Fahrenheit is: %f \n",f); return 0;}

Output:

3. C program to find the area of a triangle whose three sides are given

#include <stdio.h>#include <math.h>int main() { int a,b,c; printf("Enter the first side: "); scanf("%d",&a); printf("Enter the second side: "); scanf("%d",&b); printf("Enter the third side: "); scanf("%d",&c); if((a+b)>c && (a+c)>b && (b+c)>a){ double s=(a+b+c)/2.0; double area=sqrt(s*(s-a)*(s-b)*(s-c)); printf("Area of the triangle is: %f \n", area); }else printf("Area of the triangle does not exist. \n"); return 0;}

Output:

4. C program to find out the average of a set of integers

#include <stdio.h>int main() { int count; printf("Enter the count of numbers: "); scanf("%d",&count); int i = 0; float sum = 0; for(i=0;i<count;i++){ printf("Enter an integer: "); int x; scanf("%d",&x); sum = sum + x; } float avg = sum/count; printf("The average is: %f \n",avg); return 0;}

Output:

5. C program to find the product of a set of real numbers

#include <stdio.h>int main() { int count; printf("Enter the count of real numbers: "); scanf("%d",&count); int i = 0; float product = 1.0; for(i=0;i<count;i++){ printf("Enter a real number: "); float x; scanf("%f",&x); product = product * x; } printf("The product of the numbers is: %f \n",product); return 0;}

Output:

6. C program to find the circumference and area of a circle with a given radius

#include <stdio.h>#include <math.h>int main() { double radius; printf("Enter the radius of the circle: "); scanf("%lf",&radius); double c = 2 * M_PI * radius; double area = M_PI * radius * radius; printf("The circumference of the circle is: %lf \n",c); printf("The area of the circle is: %lf \n",area); return 0;}

Output:

7. C program to check whether the given integer is a multiple of 5

#include <stdio.h>int main() { int myNumber; printf("Enter a number: "); scanf("%d",&myNumber); if(myNumber%5==0){ printf("%d is a multiple of 5. \n",myNumber); }else{ printf("%d is not a multiple of 5. \n",myNumber); } return 0;}

Output:

8. C program to check whether the given integer is a multiple of both 5 and 7

#include <stdio.h>int main() { int myNumber; printf("Enter a number: "); scanf("%d",&myNumber); if((myNumber%5==0)&&(myNumber%7==0)){ printf("%d is a multiple of both 5 and 7. \n",myNumber); }else{ printf("%d is not a multiple of both 5 and 7. \n",myNumber); } return 0;}

Output:

9. C program to find the average of 5 numbers using while loop

#include <stdio.h>int main() { int count = 0; int sum = 0; while(count<5){ printf("Enter an integer: \n"); int number; scanf("%d",&number); sum = sum+number; count++; } double avg = (double)sum/(double)count; printf("The average is : %lf",avg); return 0;}

Output:

10. C program to display the given integer in a reverse manner

#include <stdio.h>int main() { int myNumber; printf("Enter a number: "); scanf("%d",&myNumber); int rev = 0; while(myNumber!=0){ int digit = myNumber%10; rev = (rev*10)+digit; myNumber = myNumber/10; } printf("The reverse of the number is %d \n",rev); return 0;}

Output:

11. C program to find the geometric mean of n numbers

#include <stdio.h>#include <math.h>int main() { int count, c = 0; double p = 1.0; printf("Enter the number of values: "); scanf("%d",&count); while((c<count)){ printf("Enter a real number: "); double x; scanf("%lf",&x); c = c+1; p = p * x; } double gm = pow(p,1.0/count); printf("The geometric mean is: %lf",gm); return 0;}

Output:

12. C program to find the sum of the digits of an integer using a while loop

#include <stdio.h>int main() { int number, sum = 0; printf("Enter an integer: "); scanf("%d",&number); while(number!=0){ int digit = number%10; sum = sum+digit; number = number/10; } printf("Sum of digits is: %d \n", sum); return 0;}

Output:

13. C program to display all the multiples of 3 within the range 10 to 50

#include <stdio.h>int main() { for(int i=10;i<50;i++){ if(i%3==0) printf("%d \n",i); } return 0;}

Output:

14. C program to display all integers within the range 100-150 whose sum of digits is an even number

#include <stdio.h>int main() { for(int i=100;i<150;i++){ int num = i; int sum = 0; while(num!=0){ int digit = num%10; sum = sum + digit; num = num/10; } if(sum%2==0){ printf("%d \n",i); } } return 0;}

Output:

15. C program to check whether the given integer is a prime number or not

#include <stdio.h>int main() { printf("Enter an integer greater than 1: "); int number; scanf("%d",&number); int isprime = 1; for(int i=2;i<(number/2);i++){ if(number%i==0){ isprime = 0; break; } } if(isprime==1){ printf("%d is a prime number",number); }else{ printf("%d is not a prime number",number); } return 0;}

Output:

16. C program to generate the prime numbers from 1 to N

#include <stdio.h>int main() { int number; printf("Enter range: "); scanf("%d",&number); for (int num = 2; num <= number; num++){ int isPrime = 1; for (int i=2; i <= num/2; i++){ if( num % i == 0){ isPrime = 0; break; } } if (isPrime == 1) printf("%d \n",num); } return 0;}

Output:

17. C program to print the numbers from a given number n till 0 using recursion

#include <stdio.h>void print_till_zero();int main() { print_till_zero(7); return 0;}void print_till_zero(int n){ if(n==0) return; printf("%d \n",n); n=n-1; print_till_zero(n);}

Output:

18. Cprogram to find the factorial of a number using recursion

#include <stdio.h>int fact();int main() { printf("%d \n",fact(6)); return 0;}int fact(int n){ int f; if(n==1) f=1; else f = n * fact(n-1); return f;}

Output:

19. C program to display the sum of n numbers using an array

#include <stdio.h>int main() { int count; printf("Enter the count of numbers: "); scanf("%d",&count); int numbers[count]; int sum=0; for(int i=0;i<count;i++){ printf("Enter the number: "); int x; scanf("%d",&x); numbers[i] = x; } for(int i = 0; i < count; i++) { sum = sum + numbers[i]; } printf("Sum of all the elements of the array: %d \n", sum); return 0;}

Output:

20. C program to find the number of odd numbers in an array

#include <stdio.h>int main() { int numbers[] = {8,3,1,6,2,4,5,9}; int count = 0; int size = sizeof numbers / sizeof numbers[0]; for(int i=0;i<size;i++){ if(numbers[i]%2!=0) count++; } printf("The count of odd numbers in the list is: %d \n",count); return 0;}

Output:

21. C program to find the largest number in an array without using built-in functions

#include <stdio.h>int main() { int numbers[] = {3,8,1,7,2,9,5,4}; int largest = numbers[0]; int position = 0; int size = sizeof numbers / sizeof numbers[0]; for(int i=0;i<size;i++){ if(numbers[i]>largest){ largest = numbers[i]; position = i; } } printf("The largest element is %d which is found at position %d \n",largest,position); return 0;}

Output:

22. C program to insert a number to any position in an array

#include <stdio.h>int main() { int x,y; int numbers[] = {3,4,1,9,6,2,8}; int size = sizeof numbers / sizeof numbers[0]; for(int i=0;i<size;i++){ printf("%d ",numbers[i]); } printf("\nEnter the number to be inserted: "); scanf("%d",&x); printf("Enter the position: "); scanf("%d",&y); for(int i=size-1;i>y;i--){ numbers[i] = numbers[i-1]; } numbers[y] = x; for(int i=0;i<size;i++){ printf("%d ",numbers[i]); } return 0;}

Output:

23. C program to check whether a number is palindrome or not

#include <stdio.h> int main() { int n,r,sum=0,temp; printf("Enter a number: "); scanf("%d",&n); temp=n; while(n>0){ r=n%10; sum=(sum*10)+r; n=n/10; } if(temp==sum) printf("It's a palindrome number."); else printf("It's not a palindrome number."); return 0; } 

Output:

24. Cprogram to implement matrix addition

#include <stdio.h> int main() { //creating two matrices int a[3][3]={{8,5,1},{9,3,2},{4,6,3}}; int b[3][3]={{8,5,3},{9,5,7},{9,4,1}}; //defining the matrix to store the sum of two matrices int c[3][3]; //adding 2 matrices for(int i=0;i<3;i++){ for(int j=0;j<3;j++){ c[i][j]=a[i][j]+b[i][j]; printf("%d ",c[i][j]); } printf("\n"); } return 0; } 

Output:

25. C program to implement matrix multiplication

#include <stdio.h> int main() { //creating two matrices int a[3][3]={{8,5,1},{9,3,2},{4,6,3}}; int b[3][3]={{8,5,3},{9,5,7},{9,4,1}}; //defining the matrix to store the product of two matrices int c[3][3]; //multiplying 2 matrices for(int i=0;i<3;i++){ for(int j=0;j<3;j++){ c[i][j]=0; for(int k=0;k<3;k++){ c[i][j]+=a[i][k]*b[k][j]; } printf("%d ",c[i][j]); } printf("\n"); } return 0; } 

Output:

26. C program to check leap year

#include <stdio.h> int main() { printf("Enter the year you want to check: "); int year; scanf("%d",&year); int leap = 0; // if the year is divided by 4 if (year % 4 == 0) { // if the year is century if (year % 100 == 0) { // if year is divided by 400, then it is a leap year if (year % 400 == 0) leap = 1; else leap = 0; } // if the year is not century else leap = 1; } else leap = 0; if(leap==1) printf("%d is a leap year.",year); else printf("%d is not a leap year.",year); return 0; } 

Output:

27. C program to find the Nth term in a Fibonacci series using recursion

#include <stdio.h> int main() { int n; printf("Enter the position(N): "); scanf("%d",&n); printf("\nNth Fibonacci Number is: %d",NthFibonacciNumber(n)); return 0; } int NthFibonacciNumber(int n){ if(n==1) return 0; else if(n==2) return 1; else return NthFibonacciNumber(n-1)+NthFibonacciNumber(n-2);}

Output:

28. C program to printthe Fibonacci series using iteration

#include <stdio.h> int main() { int n1=0,n2=1; printf("Enter the number of terms in the sequence: "); int count; scanf("%d",&count); int n3,i; //printing 0 and 1 printf("%d %d ",n1,n2); //printing from 2 because 0 and 1 are already printed for(i=2;i<count;++i){ n3=n1+n2; printf("%d ",n3); n1=n2; n2=n3; } return 0; } int NthFibonacciNumber(int n){ if(n==1) return 0; else if(n==2) return 1; else return NthFibonacciNumber(n-1)+NthFibonacciNumber(n-2);}

Output:

29. C program to implement a calculator to do basic arithmetic operations

#include <stdio.h> int main() { int firstNumber, secondNumber, opt, add, sub, mul; double div; printf("Enter first number: "); scanf("%d",&firstNumber); printf("Enter second number: "); scanf("%d",&secondNumber); printf("Enter 1 for addition \n"); printf("Enter 2 for subtraction \n"); printf("Enter 3 for multiplication \n"); printf("Enter 4 for division \n"); printf("Enter 5 to Exit \n"); int option; scanf("%d",&option); switch(option){ case 1: add = firstNumber + secondNumber; printf("Result: %d",add); break; case 2: sub = firstNumber - secondNumber; printf("Result: %d",sub); break; case 3: mul = firstNumber * secondNumber; printf("Result: %d",mul); break; case 4: div = (double)firstNumber / secondNumber; printf("Result: %lf",div); break; case 5: exit(0); } }

Output:

30. C Program to Find the Sum of Even Numbers

#include <stdio.h> int main() { int sum=0; for(int i=1;i<=100;i++){ if(i%2==0){ sum = sum + i; } } printf("The sum of even numbers from 1-100 is: %d",sum); }

Output:

31. C program to implement linear search

#include <stdio.h> int main() { int numbers[] = {4,2,7,1,8,3,6}; int flag = 0; printf("Enter the number to be found out: "); int x; scanf("%d",&x); int size = sizeof numbers/ sizeof numbers[0]; for(int i=0;i<size;i++){ if (x==numbers[i]){ printf("Successful search, the element is found at position %d", i); flag = 1; break; } } if(flag==0){ printf("Oops! Search unsuccessful"); } }

Output: