Free all codes

Simple interest

#include < stdio.h >

void main()
{
int amount, rate, time, ans;

printf("\nEnter Principal Amount : ");
scanf("%d", &amount);

printf("\nEnter Rate of Interest : ");
scanf("%d", &rate);

printf("\nEnter Period of Time : ");
scanf("%d", &time);

ans = (amount * rate * time)/100;
/*Simple interest formula*/
printf("\nSimple Interest : %d",ans);
}

Area of Circle

#include < stdio.h >
#include < math.h >
#define PI 3.142

void main()
{
float radius, area;

printf("Enter the radius of a circle \n");
scanf("%f", &radius);

area = PI * pow(radius, 2);

printf("Area of a circle = %5.2f\n", area);
}

Area of Rectangle

#include < stdio.h >
#include < conio.h >

int main() {
int length, breadth, area;

printf("\nEnter the Length of Rectangle : ");
scanf("%d", &length);

printf("\nEnter the Breadth of Rectangle : ");
scanf("%d", &breadth);

area = length * breadth;
printf("\nArea of Rectangle : %d", area);

return (0);
}

Area of Square

#include < stdio.h >

int main() {
int side, area;

printf("\nEnter the Length of Side : ");
scanf("%d", &side);

area = side * side;
printf("\nArea of Square : %d", area);

return (0);
}

Volume of Cube

#include < stdio.h >

void main()
{
float a;
float surface_area,volume;

printf("Enter size of any side of a cube : ");
scanf("%f",&a);

surface_area = 6 * (a * a);
volume = a * a * a;

printf("Surface area of cube is: %.3f",surface_area);
printf("\nVolume of cube is : %.3f",volume);
}

Volume of Cylinder

#include < stdio.h >

void main()
{
float vol,pie=3.14;
float r,h;

printf("ENTER THE VALUE OF RADIOUS :- ");
scanf("%f",&r);
printf("ENTER THE VALUE OF HEIGHT :- ");
scanf("%f",&h);

vol = pie * r * r * h;
printf("VOLUME OF CYLINDER IS :- %3.2f ",vol);
}

Volume of Sphere

#include < stdio.h >
#include < math.h >

void main()
{
float radius,pie,volume;
pie=3.1416;

printf("Enter the radius:");
if(scanf("%f",&radius)==1)
{
volume=(4/3)*pie*pow(radius,3);
printf("The volume is :%6.2f",volume);
}
else
{
printf("error ,enter correct value");
}
}

Leap year

#include < stdio.h >

int main()
{
  int year;

  printf("Enter a year to check if it is a leap year\n");
  scanf("%d", &year);

  if ( year%400 == 0)
  printf("%d is a leap year.\n", year);
  else if ( year%100 == 0)
  printf("%d is not a leap year.\n", year);
  else if ( year%4 == 0 )
  printf("%d is a leap year.\n", year);
  else
  printf("%d is not a leap year.\n", year);

  return 0;
}

HCF and LCM

#include < stdio.h >

long gcd(long, long);
int main() {
  long x, y, hcf, lcm;

  printf("Enter two integers\n");
  scanf("%ld%ld", &x, &y);

  hcf = gcd(x, y);
  lcm = (x*y)/hcf;

  printf("Greatest common divisor of %ld and %ld = %ld\n", x, y, hcf);
  printf("Least common multiple of %ld and %ld = %ld\n", x, y, lcm);

  return 0;
}

/*if 1st no is 0 then 2nd no is gcd
make 2nd no 0 by subtracting smallest from largest and return 1st no as gcd*/
long gcd(long x, long y) {
  if (x == 0) {
  return y;
  }

  while (y != 0) {
  if (x > y) {
    x = x - y;
  }
  else {
    y = y - x;
  }
}

return x;
}

Reverse number

#include < stdio.h >

int main()
{
  int n, reverse = 0;

  printf("Enter a number to reverse\n");
  scanf("%d",&n);

  while (n != 0)
{
  reverse = reverse * 10;
  reverse = reverse + n%10;
  n = n/10;
}
/*taking unit place digit of no and moving to reverse
Dividing the no to discard unit place digit*/

  printf("Reverse of entered number is = %d\n", reverse);

  return 0;
}

Prime numbers

#include < stdio.h >

int check_prime(int);

main()
{
  int i, n, result;

  printf("Enter the number of prime numbers required\n");
  scanf("%d",&n);
  printf("First %d prime numbers are :\n", n);

  for(i=0; i < n; i++){
  result = check_prime(i);
  /*if i is prime then it will return 1*/

  if ( result == 1 )
    printf("%d \n", i);
  }
  return 0;
}

int check_prime(int a)
{
  int c;
  /*starting from 2, if no is completely divisible by any no then it is not prime*/
  for ( c = 2 ; c <= a - 1 ; c++ )
  {
  if ( a%c == 0 )
    return 0;
  }
  if ( c == a )
    return 1;
}

Perfect Number

#include < stdio.h >

int main(){
int n,i=1,sum=0;

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

while(i < n){
if(n%i==0)
sum=sum+i;
i++;
}

if(sum==n)
printf("%d is a perfect number",i);
else
printf("%d is not a perfect number",i);

return 0;
}

#include < stdio.h >

void main()
{
int gross_salary, basic, da, ta;

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

da = (10 * basic)/100;
ta = (12 * basic)/100;

gross_salary = basic + da + ta;
printf("\nGross salary : %d",gross_salary);
}

Temperature conversion

#include < stdio.h >

void main()
{
int from , to;
float value;

printf("Temperature Conversion\n");
printf("Enter no of Unit to covert from : \n 1.celcius\n 2. Farenheit\n 3. Kelvin");
scanf("%d",&from);

printf("Enter no of Unit to covert to : \n 1.celcius\n 2. Farenheit\n 3. Kelvin");
scanf("%d",&to);

printf("Enter The value to convert: ");
scanf("%f",&value);

/*converting given value from specified unit to Kelvin*/
switch(from) {
  case 1:
  value= value + 273.15; break;
  case 2:
  value= (value+459.67)*5/9; break;
  case 3: break;
  default: break;
  }

/*converting value from Kelvin to specified unit*/
switch(to) {
  case 1:
  value= value-273.15; break;
  case 2:
  value= value*9/5-459.67; break;
  case 3: break;
  default: break;
  }

printf("Converted Value : %f", value);
}

#include < stdio.h >

int main()
{
  int a;

  printf("Enter an integer\n");
  scanf("%d", &a);
  //takes an integer from user

  printf("Integer that you have entered is %d\n", a);

  return 0;
}

#include < stdio.h >

void main()
{
  int height, base;
  float ans;/*ans may come in fractions*/

  printf("Enter height and base");
  scanf("%d %d",&height, &base);
  ans= (1/2)*height*base;
  /* mathematical formula*/

  printf("Area if triangle is %f",ans);
}

#include < stdio.h >

main()
{
  int n;

  printf("Enter an integer\n");
  scanf("%d",&n);

/*if n is completely divisible by 2 then prints even otherwise n is odd*/
  if ( n%2 == 0 )
    printf("Even\n");
  else
    printf("Odd\n");

  return 0;
}

#include < stdio.h >

int main()
{
  int first, second, add, subtract, multiply;
  float divide;

  printf("Enter two integers\n");
  scanf("%d%d", &first, &second);

  add = first + second;
  subtract = first - second;
  multiply = first * second;
  divide = first / (float)second;
  //typecasting

  printf("Sum = %d\n",add);
  printf("Difference = %d\n",subtract);
  printf("Multiplication = %d\n",multiply);
  printf("Division = %.2f\n",divide);

  return 0;
}

#include < stdio.h >

int main()
{
  int n, sum = 0, c, value;

  printf("Enter the number of integers you want to add\n");
  scanf("%d", &n);

  printf("Enter %d integers\n",n);

  for (c = 1; c <= n; c++)
  {
  scanf("%d",&value);
  sum = sum + value;
  /*adding each no in sum*/
  }

  printf("Sum of entered integers = %d\n",sum);

  return 0;
}

#include < stdio.h >

void main()
{
int a,b,c;

printf("enter any three numbers:\n");
scanf("%d%d%d",&a, &b, &c);
if(a>b&&a>c)
/*if a is greater than b & c*/
printf("greatest number is: %d",a);
else if(b>c)
/*if not a then if b is greater than c*/
printf("greatest number is: %d",b);
else
/*if a & b are not greater*/
printf("greatest number is: %d",c);
}

#include < stdio.h >

int main()
{
  int x, y, temp;

  printf("Enter the value of x and y\n");
  scanf("%d%d", &x, &y);

  printf("Before Swapping\nx = %d\ny = %d\n",x,y);

  temp = x;
  x = y;
  y = temp;
/*using temp to swap
storing x to temp and y to x then moving temp to y*/

  printf("After Swapping\nx = %d\ny = %d\n",x,y);

  return 0;
}

#include < stdio.h >
void main()
{
  int marks;
  printf("Enter your marks : ");
  scanf("%d",&marks);

  if(marks>100)
/*marks greater than 100*/
    printf("Not valid marks");

  else if(marks>=80)
/*marks between 80 & 99*/
    printf("your grade is A");

  else if(marks >=70)
/*marks between 70 & 79*/
    printf("your grade is B");

  else if(marks>=50)
/*marks between 50 & 69*/
    printf("your grade is C");

  else if(marks>=35)
/*marks between 35 & 49*/
    printf("your grade is D");

  else
/*marks less than 35*/
    printf("your grade is E");
}

#include < stdio.h >

void main()
{
int s1, s2, s3, s4, s5, sum, total = 500;
float per;
printf("\nEnter marks of 5 subjects : ");
scanf("%d %d %d %d %d", &s1, &s2, &s3, &s4, &s5);

sum = s1 + s2 + s3 + s4 + s5;
printf("\nSum : %d", sum);

per = (sum * 100)/500;
/* percentage formula*/
printf("\nPercentage : %f", per);
}

#include < stdio.h >

int main()
{
  int first, second, sum;

  printf("Enter two integers to add\n");
  scanf("%d%d", &first, &second);

  sum = first + second ;
/*Adding contents of first and second and storing in sum*/

  printf("Sum of entered numbers = %d\n",sum);

  return 0;
}

#include < stdio.h >
//compiler to include std input output header file.

int main()
{
  printf("Hello world\n");
  //prints Hello world on user screen
  return 0;
  //return the value zero to the OS.
}

#include < stdio.h >

int main()
{
  int n, sum = 0, remainder;

  printf("Enter an integer\n");
  scanf("%d",&n);

  while(n != 0)
  {
  remainder = n % 10;
 /*stores unit place digit to remainder*/
  sum = sum + remainder;
  n = n / 10;
 /*dividing no to discard unit place digit*/
  }

  printf("Sum of digits of entered number = %d\n",sum);

  return 0;
}

#include <stdio.h>
int main()
{
int n, sum = 0, c, value;
printf("Enter the number of integers you want to add\n");
scanf("%d", &n);
printf("Enter %d integers\n",n);
for (c = 1; c <= n; c++)
{
scanf("%d",&value);
sum = sum + value;
}
printf("Sum of entered integers = %d\n",sum);
return 0;
}