Question 1: Find the largest number among the three numbers.
// C Program to find
// Largest of three numbers
#include
int main() {
int a = 1, b = 2, c = 3;
// condition for a is greatest
if (a > b && a > c)
printf("%d", a);
// condition for b is greatest
else if (b > a && b > c)
printf("%d", b);
// remaining conditions
// c is greatest
else
printf("%d", c);
return 0;
}
Question 2: Write a Program to check whether a number is prime or not.
// C Program for
// Checking value is
// Prime or not
#include
int main() {
int N = 91;
int flag = 0;
// Iterate from 2 to N/2
for (int i = 2; i <= N / 2; i++) {
// If n is divisible by any number between 2 and
// n/2, it is not prime
if (N % i == 0) {
flag = 1;
break;
}
}
if (flag == 0)
printf("Not a Prime Number");
else
printf("Is a Prime Number");
return 0;
}
Question 3: Write a C program to calculate Compound Interest.
// C program to calculate Compound Interest
#include
// For using pow function we must
// include math.h
#include
// Driver code
int main()
{
// Principal amount
double principal = 2300;
// Annual rate of interest
double rate = 7;
// Time
double time = 4;
// Calculating compound Interest
double amount
= principal * ((pow((1 + rate / 100), time)));
double CI = amount - principal;
printf("Compound Interest is : %lf", CI);
return 0;
}
Question 4: Write a Program in C to Swap the values of two variables without
using any extra variable.
// C Program to
// Swap two numbers
// No Extra Space
#include
int main()
{
int x = 10;
int y = 20;
printf("x: %d , y: %d\n", x, y);
// Code to swap 'x' and 'y'
x = x + y;
y = x - y;
x = x - y;
printf("x: %d , y: %d\n", x, y);
return 0;
}
Question 5: Write a Program to Replace all 0’s with 1’s in a Number.
// C Program for
// Replacing 0 to 1
#include
#include
int main()
{
int N = 102301;
int ans = 0;
int i = 0;
while (N != 0) {
// Condition to change value
if (N % 10 == 0)
ans = ans + 1 * pow(10, i);
else
ans = ans + (N % 10) * pow(10, i);
N = N / 10;
i++;
}
printf("%d", ans);
return 0;
}
Question 6: Write a Program to convert the binary number into a decimal
number.
// C Program for converting
// binary to decimal
#include
int main()
{
int N = 11011;
// Initializing base value a to 1
int a = 1;
int ans = 0;
while (N != 0) {
ans = ans + (N % 10) * a;
N = N / 10;
a = a * 2;
}
printf("%d", ans);
return 0;
}
Question 7: Write a Program to check if the year is a leap year or not.
// C Program to check
// Year is leap year or not
#include
// Function Declaration to check leap year
void leap_year(int year) {
// If a year is multiple of 400, then leap year
if (year % 400 == 0)
printf("%d is a leap year.\n", year);
// If a year is multiple of 100, then not a leap year
else if (year % 100 == 0)
printf("%d is not a leap year.\n", year);
// If a year is multiple of 4, then leap year
else if (year % 4 == 0)
printf("%d is a leap year.\n", year);
// Not leap year
else
printf("%d is not a leap year.\n", year);
}
int main() {
leap_year(2000);
leap_year(2002);
leap_year(2008);
return 0;
}
Question 8: Write a program to Factorial of a Number.
// C Program to calculate
// Factorial of a number
#include
// Calculating factorial using iteration
void factorial_iteration(int N) {
unsigned long long int ans = 1;
for (int i = 1; i <= N; i++) {
ans = ans * i;
}
printf("Factorial of %d is %lld\n", N, ans);
}
// Calculating factorial using recursion
int factorial(int N) {
if (N == 0)
return 1;
// Recursive call
return N * factorial(N - 1);
}
int main() {
int n;
n = 13;
factorial_iteration(n);
n = 9;
printf("Factorial of %d using recursion:%d\n", n, factorial(n));
return 0;
}
Question 9: Write a Program to Check if a number is an Armstrong number or not.
// C program to check if number
// is Armstrong number or not
#include
// Function to calculate x raised to the power y
int power(int x, unsigned int y) {
if (y == 0)
return 1;
if (y % 2 == 0)
return power(x, y / 2) * power(x, y / 2);
return x * power(x, y / 2) * power(x, y / 2);
}
// Function to calculate order of the number
int order(int n) {
int res = 0;
while (n) {
res++;
n = n / 10;
}
return res;
}
// Function to check whether the given number is
// Armstrong number or not
int isArmstrong(int x) {
// Calling order function
int n = order(x);
int temp = x, sum = 0;
while (temp) {
int r = temp % 10;
sum += power(r, n);
temp = temp / 10;
}
// If satisfies Armstrong condition
if (sum == x)
return 1;
else
return 0;
}
// Driver Program
int main() {
int x = 120;
if (isArmstrong(x) == 1)
printf("True\n");
else
printf("False\n");
x = 1634;
if (isArmstrong(x) == 1)
printf("True\n");
else
printf("False\n");
return 0;
}
Question 10: Write a program to Find all the roots of a quadratic equation in C.
// C program to find roots
// of a quadratic equation
#include
#include
#include
// Prints roots of quadratic equation ax*2 + bx + x
void find_roots(int a, int b, int c) {
// If a is 0, then equation is not quadratic, but
// linear
if (a == 0) {
printf("Invalid");
return;
}
int d = (b * b) - (4 * a * c);
double sqrt_val = sqrt(abs(d));
if (d > 0) {
printf("Roots are real and different \n");
printf("%f\n%f", (double)(-b + sqrt_val) / (2 * a),
(double)(-b - sqrt_val) / (2 * a));
}
else if (d == 0) {
printf("Roots are real and same \n");
printf("%f", -(double)b / (2 * a));
}
else // d < 0
{
printf("Roots are complex \n");
printf("%f + i%f\n%f - i%f", -(double)b / (2 * a),
sqrt_val / (2 * a), -(double)b / (2 * a),
sqrt_val / (2 * a));
}
}
// Driver code
int main() {
int a = 1, b = -16, c = 1;
// Function call
find_roots(a, b, c);
return 0;
}
