#include<stdio.h>


   /* lower:  convert c to lower case; ASCII only */
   int lower(int c)
   {
       if (c >= 'A' && c <= 'Z')
           return c + 'a' - 'A';
       else
           return c;
   }

main()
{

putchar('\n');
putchar(lower('A'));
putchar('\n');
}