INTERESTING FACT ON C

Below is one of the interesting facts about C programming:

1) The case labels of a switch statement can occur inside if-else statement

#include

int main()
{
    int a = 2, b = 2;
    switch(a)
    {
    case 1:
        ;

        if (b==5)
        {
        case 2:
            printf("GeeksforGeeks");
        }
    else case 3:
    {

    }
    }
}
Run on IDE
Output :GeeksforGeeks

FACTORIAL

#include
int main()
{
    int n, i;
    unsigned long long factorial = 1;

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

    // show error if the user enters a negative integer
    if (n < 0)
        printf("Error! Factorial of a negative number doesn't exist.");

    else
    {
        for(i=1; i<=n; ++i)
        {
            factorial *= i;              // factorial = factorial*i;
        }
        printf("Factorial of %d = %llu", n, factorial);
    }

    return 0;
}

               

1.In a file contains the line "I am a boy\r\n" then on reading this line into the array str using fgets(). What will str contain?

A.            "I am a boy\r\n\0"

B.            "I am a boy\r\0"

C.            "I am a boy\n\0"

D.            "I am a boy"

TRY  IT YOURSELF

Answer: Option C

Explanation:

Declaration: char *fgets(char *s, int n, FILE *stream);

fgets reads characters from stream into the string s. It stops when it reads either n - 1 characters or a newline character, whichever comes first.

Therefore the  string str  contain “ I am a boy\n\0”.

MAGIC SQUARE PUZZLE

/*
 * C Program to Solve the Magic Squares Puzzle without using 
 * Recursion
 */
#include

void magicsq(int, int [][10]);

int main( )
{
    int size;
    int a[10][10];

    printf("Enter the size: ");
    scanf("%d", &size);
    if (size % 2 == 0)
    {
        printf("Magic square works for an odd numbered size\n");
 A   }
    else
    {
        magicsq(size, a);
    }
    return 0;
}

void magicsq(int size, int a[][10])
{
    int sqr = size * size;
    int i = 0, j = size / 2, k;

    for (k = 1; k <= sqr; ++k) 
    {
        a[i][j] = k;
        i--;
        j++;

        if (k % size == 0) 
        { 
            i += 2; 
            --j; 
        }
        else 
        {
            if (j == size) 
            {
                j -= size;
            }
            else if (i < 0)
            {
                i += size;
            }
        }
    }
    for (i = 0; i < size; i++)
    {
        for (j = 0; j < size; j++)
        {
            printf("%d  ", a[i][j]);
        }
        printf("\n");
    }
}
RUN IT..............

ALGEBRA MAGIC

#include
#include

int main()
{ 
 int x,y;
 printf("Think of a munber Between 60 and 100 .\nProvided The number should not consist of the values 0&1.\nPress Enter Key When Ready");
 getch();
 printf("\nNow add the number with its reverse.\neg.62+26\nif the number you thought was 62.\npress Enter when ready.");
 getch();
 printf("\nEnter the Middle value of your answer = ");
 scanf("%d",&x);
 y=100+(x*10)+(x-1);
 printf("The value you got is = %d",y);
 getch();
}

Run this and see the magic !!!!!!!

More on printf

What will be the output of following code 

#include

int main()
{

         printf("%d",printf("computer"));

         return (0);

}

Automorphic Numbers

Automorphic Numbers

In mathematics an automorphic number (sometimes referred to as a circular number) is a number whose square "ends" in the same digits as the number itself. For example, 5² = 25, 6² = 36, 76² = 5776, and 890625² = 793212890625, so 5, 6, 76 and 890625 are all automorphic numbers. The only automorphic Kaprekar number is 1, because the square of a Kaprekar number cannot start with zero.

The sequence of automorphic numbers begins 1, 5, 6, 25, 76, 376, 625, 9376, ... (sequence A003226 in the OEIS).