This snippet has a will convert Decimal number to Binary number In C++

This snippet has a will convert Decimal number to Binary number.

// coverts decimal to binary
// vishesh
// 21/05/2005

#include 

char* DEC_BIN(int);

int main()
{
 //
 int num;
 std::cout << "Enter a number: ";
 std::cin   >> num;
 std::cout << DEC_BIN(num);
 std::cin.get();
 return 0;
}

char* DEC_BIN(int dec)
{
 using namespace std;

 char *rtn;

 int prev, len, temp, *bin;
 
 prev = dec;
 
 for(int i=0;prev!=0;i++)
 { 
  prev = prev/2;
  len=i;
 }

 bin = new int[len+1];

 prev = dec;

 for(int i=0;prev!=0;i++)
 {
  bin[i] = prev%2;
  prev = prev/2;
  len=i;
 }

 bin[len+1] = prev%2;
 len++;

 for(int i=0;i < len/2;i++)
 {
  temp=bin[i];
  bin[i]=bin[len-1-i];
  bin[len-1-i]=temp;
 }

 rtn = new char[len+1];
 
 for(int i=0;i<len;i++)
 {
  rtn[i]=bin[i]+'0';
  rtn[i+1]='\0';
 }
 
 return rtn;
}