c programming examples ON UNIT ONE

1)Swapping of two numbers without third variable

#include
 
main()
{
   int a, b;
 
   printf("Enter two numbers to swap ");
   scanf("%d%d",&a,&b);
 
   a = a + b;
   b = a - b;
   a = a - b;
 
   printf("a = %d\nb = %d\n",a,b);
   return 0;
}

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2)C program to perform addition, subtraction, multiplication and division

#include 
 
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;
}
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3)c program to reverse a number

#include
 
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;
   }
 
   printf("Reverse of entered number is = %d\n", reverse);
 
   return 0;
}
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4)Palindrome number algorithm

1. Get the number from user.
2. Reverse it.
3. Compare it with the number entered by the user.
4. If both are same then print palindrome number
5. Else print not a palindrome number.

Palindrome number program c

#include
 
main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

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5)armstrong number c program

#include
#include
 
main()
{
   int number, sum = 0, temp, remainder;
 
   printf("Enter a number\n");      
   scanf("%d",&number);
 
   temp = number;
 
   while( temp != 0 )
   {
      remainder = temp%10;
      sum = sum + remainder*remainder*remainder;
      temp = temp/10; 
   }
 
   if ( number == sum )
      printf("Entered number is an armstrong number.");
   else
      printf("Entered number is not an armstrong number.");         
 
   getch();
   return 0;
}
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6)add digits of number in c

#include
 
main()
{
   int n, sum = 0, remainder;
 
   printf("Enter an integer\n");
   scanf("%d",&n);
 
   while( n != 0 )
   {
      remainder = n % 10;
      sum = sum + remainder;
      n = n / 10;
   }
 
   printf("Sum of digits of entered number = %d\n",sum);
 
   return 0;
}

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7)Factorial program in c using for loop

#include
#include
 
main()
{
   int c, n, fact = 1;
 
   printf("Enter a number to calculate it's factorial\n");
   scanf("%d",&n);
 
   for( c = 1 ; c <= n ; c++ )
         fact = fact*c;
 
   printf("Factorial of %d = %d\n",n,fact);
 
   getch();
   return 0;
}

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8)

C programming code for abs

#include
#include
 
main()
{
   int number, result;
 
   printf("Enter a number to calculate it's absolute value ");
   scanf("%d",&number);
 
   result = abs(number);
 
   printf("Absolute value of %d = %d", number, result);
 
   getch();
   return 0;
}

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9)C programming code for pow

#include
#include
 
main()
{
   double a, b, result;
 
   printf("Enter a and b to calculate a^b ");
   scanf("%lf%lf",&a, &b);
 
   result = pow(a, b);
 
   printf("%lf raised to %lf = %lf", a, b, result);
 
   return 0;
}

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10)C programming code for sqrt

#include
#include
 
main()
{
   double number, result;
 
   printf("Enter a number to calculate it's square root ");
   scanf("%lf",&number);
 
   result = sqrt(number);
 
   printf("Square root of %lf = %lf", number, result);
 
   return 0;
}

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11)C programming code for log

#include
#include
 
main()
{
   double number, result;
 
   printf("Enter a number to calculate it's natural log (base is e) ");
   scanf("%lf",&number);
 
   result = log(number);
 
   printf("Natural log of %lf = %lf", number, result);
 
   return 0;
}

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