#include 

void encipher(unsigned long *v,unsigned long *w, const unsigned long *k)
{
   unsigned long       y=v[0],z=v[1],sum=0,delta=0x9E3779B9,
				a=k[0],b=k[1],c=k[2],d=k[3],n=32;

   while(n-->0)
      {
      sum += delta;
      y += (z<<4)+a ^ z+sum ^ (z>>5)+b;
      z += (y<<4)+c ^ y+sum ^ (y>>5)+d;
      }

   w[0]=y; w[1]=z;
}

void decipher(unsigned long *v,unsigned long *w, const unsigned long *k)
{
   unsigned long       y=v[0],z=v[1],sum=0xC6EF3720,
				delta=0x9E3779B9,a=k[0],b=k[1],c=k[2],
				d=k[3],n=32;

   /* sum = delta<<5, in general sum = delta * n */

   while(n-->0)
      {
      z -= (y<<4)+c ^ y+sum ^ (y>>5)+d;
      y -= (z<<4)+a ^ z+sum ^ (z>>5)+b;
      sum -= delta;
      }
   
   w[0]=y; w[1]=z;
}