hash

hash.c

#include <stdio.h>

void hash(int* bits, int bitsLen, int* out, int outLen){
  const int tt[9] = {1,2,0,0,0,1,1,2,2};
  int st[128], i, k, j, x, y, a, b, o = 0;
  for (int i=0; i<128; ++i)
    st[i] = i%3;
  for (k=0; k < bitsLen + outLen; ++k){
    for (j=0; j<32; ++j){
      if (k < bitsLen)
        st[0] = bits[k];
      for (i=j%2; i<128; i+=2){
        x = i%128;
        y = (i+1)%128;
        a = st[x];
        b = st[y];
        st[x] = tt[a*3+b];
        st[y] = tt[b*3+a];
      };
    };
    if (k >= bitsLen)
      out[o++] = (st[0] + st[1]*3 + st[2]*9 + st[3]*27) % 2;
  };
};

void printHex(int* bits, int bitsLen){
  for (int i=0; i<bitsLen/4; ++i)
    printf("%x", bits[i*4+0]*8+bits[i*4+1]*4+bits[i*4+2]*2+bits[i*4+3]);
};

void toBits(int n, int* bits, int bitsLen){
  for (int i=0; i<bitsLen; ++i)
    bits[bitsLen-i-1] = (n >> i) & 1;
};

int main(){
  const int bitsLen = 16;
  int bits[bitsLen] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

  const int outLen = 256;
  int out[outLen];

  for (int i=0; i<4096; ++i){
    toBits(i, bits, bitsLen);
    hash(bits, bitsLen, out, outLen);
    printHex(bits, bitsLen);
    printf(": ");
    printHex(out, outLen);
    printf("\n");
  };
};