bool is_pangram( const char *str)

{

    bool all_hit[25];

    memset(all_hit,0x00,sizeof(bool)*25);

    int counter = 0;

    int bit_block = 0;

    do

    {

        bit_block |= 1 << (*(str+counter) | 0x20) - 0x30);


    }while( *(str+counter) != '/0');


    return bit_block == 0x1FFFFFF ? true : false;

}