#include "stdafx.h"
 
int is_rim[64] = {
      1,   1,   1,   1,   1,   1,   1,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   0,   0,   0,   0,   0,   0,   1,
      1,   1,   1,   1,   1,   1,   1,   1
};
 
 
/* please note that this recognizer assumes that the position is legal, 
   i.e. side to move is not in check */
 
int isDraw() {
 
    /* no pawns */
    if (!b.PawnMaterial[WHITE] && !b.PawnMaterial[BLACK] ) {
 
        /* both sides have at most one minor piece - to guard against the possibility 
           of a helpmate in the corner, we do not claim an immediate draw if the king
           of the weaker side stands on the edge of the board */
 
        if ( b.PieceMaterial[WHITE] < 400 &&
             b.PieceMaterial[BLACK] < 400 &&
             ( !is_rim[b.KingLoc[WHITE] ] || b.PieceMaterial[BLACK] == 0 ) &&
             ( !is_rim[b.KingLoc[BLACK] ] || b.PieceMaterial[WHITE] == 0 )    
        )
        return 1;
 
    }
 
    /* default: no draw spotted */
    return 0;
}

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