for the 2nd one, 我的作业。（俺刚写的，还没调试：）

2)Write a function to print a number in binary form.

void BinaryPrint( long decNumber)
{

long appearanceBinNum = 0L;
long decMultiplier = 1L;
while (decNumber > 0)
{
appearanceBinNum += decMultiplier*( decNumber %2);
decNumber /= 2;
decMultiplier *= 10;
}

cout return;

}