Obj CollectPolycyc ( Obj pcp, Obj list, Obj word ) { Int ngens = INT_INTOBJ( CONST_ADDR_OBJ(pcp)[ PC_NUMBER_OF_GENERATORS ] ); Obj commute = CONST_ADDR_OBJ(pcp)[ PC_COMMUTE ]; Obj gens = CONST_ADDR_OBJ(pcp)[ PC_GENERATORS ]; Obj igens = CONST_ADDR_OBJ(pcp)[ PC_INVERSES ]; Obj pow = CONST_ADDR_OBJ(pcp)[ PC_POWERS ]; Obj ipow = CONST_ADDR_OBJ(pcp)[ PC_INVERSEPOWERS ]; Obj exp = CONST_ADDR_OBJ(pcp)[ PC_EXPONENTS ]; Obj wst = CFTLState()->WORD_STACK; Obj west = CFTLState()->WORD_EXPONENT_STACK; Obj sst = CFTLState()->SYLLABLE_STACK; Obj est = CFTLState()->EXPONENT_STACK; Obj conj=0, iconj=0; /*QQ initialize to please compiler */ Int st; Int g, syl, h, hh; Obj e, ee, ge, mge, we, s, t; Obj w, x = (Obj)0, y = (Obj)0; if( LEN_PLIST(word) == 0 ) return (Obj)0; if( LEN_PLIST(list) < ngens ) { ErrorQuit( "vector too short", 0L, 0L ); return (Obj)0; } if( LEN_PLIST(word) % 2 != 0 ) { ErrorQuit( "Length of word odd", 0L, 0L ); return (Obj)0; } st = 0; PUSH_STACK( word, INTOBJ_INT(1) ); while( st > 0 ) { w = ELM_PLIST( wst, st ); syl = INT_INTOBJ( ELM_PLIST( sst, st ) ); g = INT_INTOBJ( ELM_PLIST( w, syl ) ); if( st > 1 && syl==1 && g == GET_COMMUTE(g) ) { /* Collect word^exponent in one go. */ e = ELM_PLIST( west, st ); /* Add in. */ AddIn( list, w, e ); /* Reduce. */ for( h = g; h <= ngens; h++ ) { s = ELM_PLIST( list, h ); if( IS_INT_ZERO( s ) ) continue; y = (Obj)0; if( (e = GET_EXPONENT( h )) != (Obj)0 ) { if( !LtInt( s, e ) ) { t = ModInt( s, e ); SET_ELM_PLIST( list, h, t ); CHANGED_BAG( list ); if( (y = GET_POWER( h )) ) e = QuoInt( s, e ); } else if( LtInt( s, INTOBJ_INT(0) ) ) { t = ModInt( s, e ); SET_ELM_PLIST( list, h, t ); CHANGED_BAG( list ); if( (y = GET_IPOWER( h )) ) { e = QuoInt( s, e ); if( !IS_INT_ZERO( t ) ) e = DiffInt( e, INTOBJ_INT(1) ); e = AInvInt(e); } } } if( y != (Obj)0 ) AddIn( list, y, e ); } st--; } else { if( g == GET_COMMUTE( g ) ) { s = ELM_PLIST( list, g ); t = ELM_PLIST( est, st ); C_SUM_FIA( ge, s, t ); SET_ELM_PLIST( est, st, INTOBJ_INT(0) ); } else { /* Assume that the top of the exponent stack is non-zero. */ e = ELM_PLIST( est, st ); if( LtInt( INTOBJ_INT(0), e ) ) { C_DIFF_FIA( ee, e, INTOBJ_INT(1) ); e = ee; SET_ELM_PLIST( est, st, e ); CHANGED_BAG( est ); conj = CONST_ADDR_OBJ(pcp)[PC_CONJUGATES]; iconj = CONST_ADDR_OBJ(pcp)[PC_INVERSECONJUGATES]; C_SUM_FIA( ge, ELM_PLIST( list, g ), INTOBJ_INT(1) ); } else { C_SUM_FIA( ee, e, INTOBJ_INT(1) ); e = ee; SET_ELM_PLIST( est, st, e ); CHANGED_BAG( est ); conj = CONST_ADDR_OBJ(pcp)[PC_CONJUGATESINVERSE]; iconj = CONST_ADDR_OBJ(pcp)[PC_INVERSECONJUGATESINVERSE]; C_DIFF_FIA( ge, ELM_PLIST( list, g ), INTOBJ_INT(1) ); } } SET_ELM_PLIST( list, g, ge ); CHANGED_BAG( list ); /* Reduce the exponent. We delay putting the power onto the stack until all the conjugates are on the stack. The power is stored in y, its exponent in ge. */ y = (Obj)0; if( (e = GET_EXPONENT( g )) ) { if( !LtInt( ge, e ) ) { mge = ModInt( ge, e ); SET_ELM_PLIST( list, g, mge ); CHANGED_BAG( list ); if( (y = GET_POWER( g )) ) ge = QuoInt( ge, e ); } else if( LtInt( ge, INTOBJ_INT(0) ) ) { mge = ModInt( ge, e ); SET_ELM_PLIST( list, g, mge ); CHANGED_BAG( list ); if( (y = GET_IPOWER( g )) ) { ge = QuoInt( ge, e ); if( !IS_INT_ZERO( mge ) ) ge = DiffInt( ge, INTOBJ_INT(1) ); ge = AInvInt(ge); } } } hh = h = GET_COMMUTE( g ); /* Find the place where we start to collect. */ for( ; h > g; h-- ) { e = ELM_PLIST( list, h ); if( !IS_INT_ZERO(e) ) { if( LtInt( INTOBJ_INT(0), e ) ) { if( GET_CONJ( h, g ) ) break; } else { if( GET_ICONJ( h, g ) ) break; } } } /* Put those onto the stack, if necessary. */ if( h > g || y != (Obj)0 ) for( ; hh > h; hh-- ) { e = ELM_PLIST( list, hh ); if( !IS_INT_ZERO(e) ) { SET_ELM_PLIST( list, hh, INTOBJ_INT(0) ); if( LtInt( INTOBJ_INT(0), e ) ) { x = ELM_PLIST( gens, hh ); } else { x = ELM_PLIST( igens, hh ); C_PROD_FIA( ee, e, INTOBJ_INT(-1) ); e = ee; } PUSH_STACK( x, e ); } } for( ; h > g; h-- ) { e = ELM_PLIST( list, h ); if( !IS_INT_ZERO(e) ) { SET_ELM_PLIST( list, h, INTOBJ_INT(0) ); x = (Obj)0; if( LtInt( INTOBJ_INT(0), e ) ) x = GET_CONJ( h, g ); else x = GET_ICONJ( h, g ); if( x == (Obj)0 ) { if( LtInt( INTOBJ_INT(0), e ) ) x = ELM_PLIST( gens, h ); else x = ELM_PLIST( igens, h ); } if( LtInt( e, INTOBJ_INT(0) ) ) { C_PROD_FIA( ee, e, INTOBJ_INT(-1) ); e = ee; } PUSH_STACK( x, e ); } } if( y != (Obj)0 ) PUSH_STACK( y, ge ); } while( st > 0 && IS_INT_ZERO( ELM_PLIST( est, st ) ) ) { w = ELM_PLIST( wst, st ); syl = INT_INTOBJ( ELM_PLIST( sst, st ) ) + 2; if( syl > LEN_PLIST( w ) ) { we = DiffInt( ELM_PLIST( west, st ), INTOBJ_INT(1) ); if( EqInt( we, INTOBJ_INT(0) ) ) { st--; } else { SET_ELM_PLIST( west, st, we ); SET_ELM_PLIST( sst, st, INTOBJ_INT(1) ); SET_ELM_PLIST( est, st, ELM_PLIST( w, 2 ) ); CHANGED_BAG( west ); CHANGED_BAG( est ); } } else { SET_ELM_PLIST( sst, st, INTOBJ_INT(syl) ); SET_ELM_PLIST( est, st, ELM_PLIST( w, syl+1 )); CHANGED_BAG( est ); } } } return (Obj)0; }
ModInt operator*(ModInt rhs) const { return ModInt(*this) *= rhs; }
ModInt operator/(ModInt rhs) const { return ModInt(*this) /= rhs; }
ModInt operator-(ModInt rhs) const { return ModInt(*this) -= rhs; }
ModInt operator+(ModInt rhs) const { return ModInt(*this) += rhs; }
ModInt operator*(const ModInt& o) const { return ModInt(*this) *= o; }
ModInt operator-(const ModInt& o) const { return ModInt(*this) -= o; }
ModInt operator+(const ModInt& o) const { return ModInt(*this) += o; }