printBin.c

// using mask to convert the integer to binary. 
void printBin( int num ){ 
    int mask = 1 << 7; // 10000000 
    for( int i = 0; i < 8; ++i ){ 
        printf( "%d", ((( num & mask ) == 0 )? 0:1) ); 
        mask >>= 1; 
    } 
    printf( "\n" ); 
}