#include <iostream>
using namespace std;
void encipher(long *v, long *k)
{
long v0 = v[0], v1 = v[1];
long sum = 0;
long delta = 0x9e3779b9;
short rounds = 32;
for(long i = 0; i<rounds; i++)
{
v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + k[sum & 3]);
sum += delta;
v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + k[(sum>>11) & 3]);
}
v[0] = v0;
v[1] = v1;
}
void decipher(long* v, long *key) {
unsigned int i;
short rounds = 32;
long v0=v[0], v1=v[1], delta=0x9E3779B9, sum=delta*rounds;
for (i=0; i < rounds; i++) {
v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum>>11) & 3]);
sum -= delta;
v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
}
v[0]=v0; v[1]=v1;
}
int main(){
long data[2]; // v0 and v1, 64bits
data[0] = 1;
data[1] = 1;
long key[4]; // 4 * 4 bytes = 16bytes = 128bits
key[0] = 0x12345678;
key[1] = 0x90ABCDEF;
key[2] = 0xFEDCBA09;
key[3] = 0x87654321;
cout << "READ: \t\t" << data[0] << endl << "\t\t" << data[1] << endl;
encipher(data, key);
cout << "ENCIPHERED: \t" << data[0] << endl << "\t\t" << data[1] << endl;
decipher(data, key);
cout << "DECIPHERED: \t" << data[0] << endl << "\t\t" << data[1] << endl;
}