#include <iostream>
#ifdef GMP
#include <gmpxx.h>
#else
#include <NTL/ZZ.h>
using namespace NTL;
#endif
#include "sizes.h"

using namespace std;

int keypair(
  unsigned char *sk,unsigned long long *sklen,
  unsigned char *pk,unsigned long long *pklen
)
{
  long long i;
  for (i = 0;i < SECRETKEY_BYTES;++i) sk[i] = 0; *sklen = SECRETKEY_BYTES;
  for (i = 0;i < PUBLICKEY_BYTES;++i) pk[i] = 0; *pklen = PUBLICKEY_BYTES;
  for (i = PUBLICKEY_BYTES;i < SECRETKEY_BYTES;++i) cin >> sk[i];
#ifdef GMP
  mpz_class p;
  mpz_class a;
  mpz_class base;
  mpz_class result;
  mpz_import(a.get_mpz_t(),SECRETKEY_BYTES - PUBLICKEY_BYTES,-1,1,0,0,sk + PUBLICKEY_BYTES);
  p = "106711310550942323238863446954494903303206603796265590798875260590060843568007841918927773348877395895791048832517368787533445258799160241834659776192282820736018472427221910874308833884006430888272214561307777629540843737689598751552666502301405808925850579645658786877473119117134988654123934303586903124139";
  base = 2;
  mpz_powm(result.get_mpz_t(),base.get_mpz_t(),a.get_mpz_t(),p.get_mpz_t());
  if (mpz_sizeinbase(result.get_mpz_t(),256) > PUBLICKEY_BYTES) return -1;
  mpz_export(pk,0,-1,1,0,0,result.get_mpz_t());
  mpz_export(sk,0,-1,1,0,0,result.get_mpz_t());
#else
  ZZ a;
  ZZ p;
  ZZ base;
  ZZ result;
  base = 2;
  a = ZZFromBytes(sk + PUBLICKEY_BYTES,SECRETKEY_BYTES - PUBLICKEY_BYTES);
  conv(p,"106711310550942323238863446954494903303206603796265590798875260590060843568007841918927773348877395895791048832517368787533445258799160241834659776192282820736018472427221910874308833884006430888272214561307777629540843737689598751552666502301405808925850579645658786877473119117134988654123934303586903124139");
  result = PowerMod(base,a,p);
  BytesFromZZ(pk,result,PUBLICKEY_BYTES);
  BytesFromZZ(sk,result,PUBLICKEY_BYTES);
#endif
  return 0;
}