// This is for z=2.
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
typedef struct{short int v; unsigned char sl;} Inv;
static short f(short x){assert(0<=x && x<1024); return (1<<20)/(x+1024+1);}
static Inv T[128]; static char In[8][128];
static short g(short n){assert(0<=n && n<1024); Inv x=T[n>>3]; int q = n&7;
   return (1<<9) + x.v - In[q][x.sl];}
int main(){
  for(int i = 0; i<128; ++i) {short int t[8];
    for(int j=0; j<8; ++j) t[j] = f(8*i+j);
    {int c = 0; for(int j=1; j<8; ++j) c = 2*c + (t[j-1]>t[j]);
         T[i]=(Inv){t[0]-512, c};
    if(0) {for(int j=0; j<8; ++j) printf("%5d", t[j]); printf(" %3d=c, %4d\n", c, i);}
    else {for(int j=1; j<8; ++j) printf("%d", t[j-1]-t[j]); printf(" 0x%02x\n", i);}}}
  for(int j = 1; j<128; ++j) assert(T[j].v+1<T[j-1].v);
  for(int i = 0; i<128; ++i) {Inv y = T[i]; printf("%02x %3d %d\n", i, y.v, y.sl);
     assert(0<=y.v && y.v < 512 && 0<=y.sl && y.sl < 128);}
  for(int j=0; j<128; ++j) {int y = 0;
     for(int k = 0; k<8; ++k) {if((1<<(7-k))&j) ++y; In[k][j] = y;}}
  for(int j=0; j<128; ++j) printf("%x", (j>>4)&15); printf("\n");
  for(int j=0; j<128; ++j) printf("%x", j&15); printf("\n");
  for(int k=0; k<8; ++k) {for(int j=0; j<128; ++j) printf("%d", In[k][j]); printf("In\n");}
  for(int j=0; j<1024; ++j) if(f(j) != g(j)) exit(printf("Bad %d %d %d\n", j, f(j), g(j)));
  return 0;}