#define		MAXSTRANDS	500
#define		MAXRES		1000

molecule	m;
residue		r, rw, rc;
int		ac, rn;

string		str;
int		nstr;
int		nres[ MAXSTRANDS ];
residue		res[ MAXSTRANDS, MAXRES ];

int	getcanonicalwcdist( file f, residue rw, residue rc )
{
	atom	aw, ac;
	float	d;
	int	res_rw, res_rc, wc_pair;
	point	wN1,wN2,wN3,wN4,wN6,wO2,wO4,wO6;
	point	cN1,cN2,cN3,cN4,cN6,cO2,cO4,cO6;

	wN1.x = 0.0; wN1.y = 0.0; wN1.z = 0.0;	
	wN2.x = 0.0; wN2.y = 0.0; wN2.z = 0.0;	
	wN3.x = 0.0; wN3.y = 0.0; wN3.z = 0.0;	
	wN4.x = 0.0; wN4.y = 0.0; wN4.z = 0.0;	
	wN6.x = 0.0; wN6.y = 0.0; wN6.z = 0.0;	
	wO2.x = 0.0; wO2.y = 0.0; wO2.z = 0.0;	
	wO4.x = 0.0; wO4.y = 0.0; wO4.z = 0.0;	
	wO6.x = 0.0; wO6.y = 0.0; wO6.z = 0.0;	
	cN1.x = 0.0; cN1.y = 0.0; cN1.z = 0.0;	
	cN2.x = 0.0; cN2.y = 0.0; cN2.z = 0.0;	
	cN3.x = 0.0; cN3.y = 0.0; cN3.z = 0.0;	
	cN4.x = 0.0; cN4.y = 0.0; cN4.z = 0.0;	
	cN6.x = 0.0; cN6.y = 0.0; cN6.z = 0.0;	
	cO2.x = 0.0; cO2.y = 0.0; cO2.z = 0.0;	
	cO4.x = 0.0; cO4.y = 0.0; cO4.z = 0.0;	
	cO6.x = 0.0; cO6.y = 0.0; cO6.z = 0.0;	

	for( aw in rw ){
		if ( aw.atomname == "N1")
			wN1 = aw.pos;
		if ( aw.atomname == "N2")
			wN2 = aw.pos;
		if ( aw.atomname == "N3")
			wN3 = aw.pos;
		if ( aw.atomname == "N4")
			wN4 = aw.pos;
		if ( aw.atomname == "N6")
			wN6 = aw.pos;
		if ( aw.atomname == "O2")
			wO2 = aw.pos;
		if ( aw.atomname == "O4")
			wO4 = aw.pos;
		if ( aw.atomname == "O6")
			wO6 = aw.pos;
	}

	for( ac in rc ){
		if ( ac.atomname == "N1")
			cN1 = ac.pos;
		if ( ac.atomname == "N2")
			cN2 = ac.pos;
		if ( ac.atomname == "N3")
			cN3 = ac.pos;
		if ( ac.atomname == "N4")
			cN4 = ac.pos;
		if ( ac.atomname == "N6")
			cN6 = ac.pos;
		if ( ac.atomname == "O2")
			cO2 = ac.pos;
		if ( ac.atomname == "O4")
			cO4 = ac.pos;
		if ( ac.atomname == "O6")
			cO6 = ac.pos;
	}

	wc_pair = 0;	

	if ( ( 2.3 <= distp(wN1,cN3)) && (distp(wN1,cN3) <= 3.2 ) ) { 
		if ( ( 2.3 <= distp(wN6,cO4)) && (distp(wN6,cO4) <= 3.2 ) ) {
			wc_pair = 1;	
		}
		else {
			if ( ( 2.3 <= distp(wO6,cN4)) && (distp(wO6,cN4) <= 3.3 ) ) {
				if ( ( 2.3 <= distp(wN2,cO2)) && (distp(wN2,cO2) <= 3.2 ) ){
					wc_pair = 1;
				}
			}	
		}
	}
	else {
		if ( ( 2.3 <= distp(wN3,cN1)) && (distp(wN3,cN1) <= 3.2 ) ) {
			if ( ( 2.3 <= distp(wO4,cN6)) && (distp(wO4,cN6) <= 3.3 ) ) {
				wc_pair = 1;
			}
			else {
				if ( ( 2.3 <= distp(wN4,cO6)) && (distp(wN4,cO6) <= 3.3 ) ) {
					if ( ( 2.3 <= distp(wO2,cN2)) && (distp(wO2,cN2) <= 3.2 ) ) {
						wc_pair = 1;
					}
				}	
			}
		}
	}

	if (wc_pair) {
		for( aw in rw ){
			for( ac in rc ){
				d = distp( aw.pos, ac.pos );
				fprintf( f, "%s:%s-%s:%s %8.3f\n",
					rw.resname, aw.atomname,
					rc.resname, ac.atomname, d );
				fprintf( f, "%s:%s-%s:%s %8.3f\n",
					rc.resname, ac.atomname,
					rw.resname, aw.atomname, d );
			}
		}
	}
};

for( ac = 2; ac <= argc; ac = ac + 1 ){

	m = getpdb( argv[ ac ] );

	nstr = 0;
	str = "";
	for( r in m ){
		if( str != r.strandname  ){
			nstr = nstr + 1;
			nres[ nstr ] = 0;
		}
		nres[ nstr ] = nres[ nstr ] + 1;
		res[ nstr, nres[ nstr ] ] = r;
		str = r.strandname;
	}

	if( nstr > 2 ){
		fprintf( stderr, "skipped %s, %d strands\n",
			argv[ ac ], nstr-2 );
	}

	for( rn = 1; rn <= nres[ 1 ]; rn = rn + 1 ){
		rw = res[ 1, rn ];
		rc = res[ 2, nres[ 1 ] - rn + 1 ];
			getcanonicalwcdist( stdout, rw, rc );
	}
}