ELSE ...... IF LADDER

#include <stdio.h>
int main ()
{
      int a = 100;                        /* local variable definition */
      if( a == 10 )                       /* check the boolean condition */
 {                                              /* if condition is true then print the following */
  printf("Value of a is 10\n" );
 }
 else if( a == 20 )
 {                                              /* if 'else if' condition is true */
  printf("Value of a is 20\n" );
 }
 else if( a == 30 )
 {                                              /* if 'else if' condition is true */
  printf("Value of a is 30\n" );
 }
 else
 {                                              /* if none of the conditions is true */
  printf("None of the values is matching\n" );
 }

 printf("Exact value of a is: %d\n", a );
 return 0;
}

output :
None of the values is matching
Exact value of a is: 100