Interesting Facts about C Programming

Here we will see some interesting facts about C programming. These are like below.

• Sometimes the case labels of some switch statement can be placed inside if-else statement.

Example

#include 
main() {
   int x = 2, y = 2;
   switch(x) {
      case 1:
         ;
         if (y==5) {
            case 2:
               printf("Hello World");
         }
         else case 3: {
            //case 3 block
         }
   }
}

Output

Hello World

• The array[index] can be written as index[array]. The reason is array elements are accessed using pointer arithmetic. The value of array[5] is *(array + 5). If this is in the reverse order like 5[array], then also this is same like *(5 + array).

Example

#include 
main() {
   int array[10] = {11, 22, 33, 44, 55, 66, 77, 88, 99, 110};
   printf("array[5]: %d
", array[5]);
   printf("5[array]: %d
", 5[array]);
}

Output

array[5]: 66
5[array]: 66

• We can use <: :> in the place of square brackets [,] and in the place of curly braces {,}.

Example

#include 
main()  = ;
printf("array[5]: %d
", array<:5:>);
%>

Output

array[5]: 66

• We can use #include in some strange places. Here let us consider the file abc.txt is holding the line “The Quick Brown Fox Jumps Over The Lazy Dog”. If we include the file after printf statement, we can print that file content.

Example

#include 
main() {
   printf
   #include "abc.txt" ;
}

Output

The Quick Brown Fox Jumps Over The Lazy Dog

• We can ignore the input using %*d in scanf().

Example

#include 
main() {
   int x;
   printf("Enter two numbers: ");
      scanf("%*d%d", &x);
   printf("The first one is not taken, the x is: %d", x);

}

Output

Enter two numbers: 56 69
The first one is not taken, the x is: 69