#define W 10
#define H 10

// Recursive approach  BigLittle24d.cc  derived from BigLittle32c.cc
// Saves a factor of T! by starting from the next ministate in sequence

struct Box
{
  unsigned int r[H] ; 
};

#define littleW 2
#define bigW    4

#define bigHoptions (H-bigW+1)
#define bigWoptions (W-bigW+1)

#define littleOptions ((W-littleW+1)*(H-littleW+1))
#define bigOptions    ((W-bigW+1)*(H-bigW+1))

#define littleSection (1<<littleW)-1
// the bit string defining a little ball, in horizontal section
#define bigSection (1<<bigW)-1
// the bit string defining a big ball, in horizontal section

#include <iostream>
using namespace std;

Box little[littleOptions] ;  
Box big[bigOptions] ;  

void bitsout( unsigned int n );
void boxout( Box bj ) ;

void addMore( int t,  // number of further little guys to add
	      Box bj, // current situation, passed by value
	      int nextj,  // which new little state to start from
	      int &ok // number of successful final states so far
	      ) ; 

int main(int argc, char* argv[])
{
  int T = 3 ; // target number of small particles
  if(argc>1) {
    sscanf( argv[1], "%d", &T ) ; // put the first command-line argument in T
  }
  cout << "bigOptions = " << bigOptions << endl;
  cout << "littleOptions = " << littleOptions << endl;
  cout << "littleSection = " << littleSection << endl;
  // make all states of a little guy
  for ( int i = 0 ; i < littleOptions ; i ++ ) {
    for ( int h=0; h < H ; h ++ ) {
      little[i].r[h]=0;
    }
    int ix = i % (W-littleW+1) ; 
    int iy = i / (W-littleW+1) ;
    for ( int row = iy ; row < iy +littleW ; row ++ ) {
      little[i].r[row] = littleSection << ix ;
    }
  }
  // make all states of a big guy
  for ( int i = 0 ; i < bigOptions ; i ++ ) {
    for ( int h=0; h < H ; h ++ ) {
      big[i].r[h]=0;
    }
    int ix = i % (W-bigW+1) ; 
    int iy = i / (W-bigW+1) ;
    for ( int row = iy ; row < iy +bigW ; row ++ ) {
      big[i].r[row] = bigSection << ix ;
    }
  }
  if(0){
    for ( int j = 0 ; j < bigOptions/100 ; j ++ ) {
      cout << j << " th state of big dude" << endl;
      boxout(big[j]);
    }
    for ( int i = 0 ; i < littleOptions/100 ; i ++ ) {
      cout << i << " th state of little dude " << endl;
      boxout( little[i] );
    }
  }
  // run through all big states, showing the number of states of
  // one little guy
  cout << "Single small-particle states" <<endl;
  for ( int j = 0 ; j < bigOptions ; j ++ ) {
    Box bj    = big[j];
    int ok = 0 ;       // counts number of microstates for this j state
    Box state = bj ;   // keeps track of the complete state of emptiness
    addMore( 1 , bj , 0 , ok ) ; 
    cout << " " << ok ;
    if ( !((j+1)%(W-bigW+1)) ) cout << endl ;
  }
  int jmin=0;
  int jmax=bigOptions;
  if(0) { // show all states
  } else { // just show a slice through - one row
    jmin = (bigHoptions/2) * bigWoptions ;
    jmax = jmin + (bigWoptions+1)/2 ;
  }
  {
    cout << T << " small-particle states" <<endl;
    for ( int j = jmin ; j < jmax ; j ++ ) {
      Box bj    = big[j];
      int ok = 0 ;       // counts number of microstates for this j state
      Box state = bj ;   // keeps track of the complete state of emptiness
      addMore( T , bj , 0 , ok ) ; 
      cout << " " << ok ;
      if ( !((j+1)%(W-bigW+1))  || (j==jmax-1) ) cout << endl ;
      cout.flush();
    }
  }
  return(0);
}

void addMore( int t,  // number of further little guys to add
	      Box bj, // current situation, passed by value
	      int nextj,  // which new little state to start from
	      int &ok // number of successful final states so far
	      ) {
  if(t<=0) { cout << "unexpected t"<<t<<endl; exit(-10) ; }
  for ( int i = nextj ; i < littleOptions ; i ++ ) {
    Box bi = little[i];
    int icompatible=1;
    for ( int h=0; icompatible && (h<H) ; h++ ) {
      if ( bj.r[h] & bi.r[h] ) {
	// collision
	icompatible=0;
      } else {
	// keep going
      }
    }      
    if ( icompatible ) {
      if ( t== 1 ) {
	ok ++ ;
      } else {
	for ( int h=0; (h<H) ; h++ ) {
	  bi.r[h] |= bj.r[h] ;
	}
	addMore( t-1 , bi , i+1, ok ) ; 
      }
    }
  }
}

void boxout( Box bj ) {
  for ( int h = 0 ; h < H ; h ++ ) {
    bitsout ( bj.r[h] ) ;cout<<endl;
  }
}

void bitsout( unsigned int m )
{
  int lastbit  ; 
  unsigned int two_to_power_i ;
  
  for ( int i = W-1 ; i >= 0 ; i -- ) {
    two_to_power_i = (1<<i) ;
    lastbit = ( two_to_power_i & m ) == 0 ? 0 : 1 ;
    cout << lastbit ;
  }
}