/*
MIT License
Combination Library version 1.5
Copyright (c) 2007 Wong Shao Voon
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef __COMBINATION_H__
#define __COMBINATION_H__
namespace stdcomb
{
// Non recursive template function
template <class BidIt>
inline bool next_combination(BidIt n_begin, BidIt n_end,
BidIt r_begin, BidIt r_end)
{
bool boolmarked=false;
BidIt r_marked;
BidIt n_it1=n_end;
--n_it1;
BidIt tmp_r_end=r_end;
--tmp_r_end;
for(BidIt r_it1=tmp_r_end; r_it1!=r_begin || r_it1==r_begin; --r_it1,--n_it1)
{
if(*r_it1==*n_it1 )
{
if(r_it1!=r_begin) //to ensure not at the start of r sequence
{
boolmarked=true;
r_marked=(--r_it1);
++r_it1;//add it back again
continue;
}
else // it means it is at the start the sequence, so return false
return false;
}
else //if(*r_it1!=*n_it1 )
{
//marked code
if(boolmarked==true)
{
//for loop to find which marked is in the first sequence
BidIt n_marked;//mark in first sequence
for (BidIt n_it2=n_begin;n_it2!=n_end;++n_it2)
if(*r_marked==*n_it2) {n_marked=n_it2;break;}
BidIt n_it3=++n_marked;
for (BidIt r_it2=r_marked;r_it2!=r_end;++r_it2,++n_it3)
{
*r_it2=*n_it3;
}
return true;
}
for(BidIt n_it4=n_begin; n_it4!=n_end; ++n_it4)
if(*r_it1==*n_it4)
{
*r_it1=*(++n_it4);
return true;
}
}
}
return true;//will never reach here
}
// Non recursive template function with Pred
template <class BidIt, class Prediate>
inline bool next_combination(
BidIt n_begin,
BidIt n_end,
BidIt r_begin,
BidIt r_end,
Prediate Equal)
{
bool boolmarked=false;
BidIt r_marked;
BidIt n_it1=n_end;
--n_it1;
BidIt tmp_r_end=r_end;
--tmp_r_end;
for(BidIt r_it1=tmp_r_end; r_it1!=r_begin || r_it1==r_begin; --r_it1,--n_it1)
{
if( Equal( *r_it1, *n_it1) )
{
if(r_it1!=r_begin) //to ensure not at the start of r sequence
{
boolmarked=true;
r_marked=(--r_it1);
++r_it1;//add it back again
continue;
}
else // it means it is at the start the sequence, so return false
return false;
}
else //if(*r_it1!=*n_it1 )
{
//marked code
if(boolmarked==true)
{
//for loop to find which marked is in the first sequence
BidIt n_marked;//mark in first sequence
for (BidIt n_it2=n_begin;n_it2!=n_end;++n_it2)
if( Equal( *r_marked, *n_it2) ) {n_marked=n_it2;break;}
BidIt n_it3=++n_marked;
for (BidIt r_it2=r_marked;r_it2!=r_end;++r_it2,++n_it3)
{
*r_it2=*n_it3;
}
return true;
}
for(BidIt n_it4=n_begin; n_it4!=n_end; ++n_it4)
if( Equal(*r_it1, *n_it4) )
{
*r_it1=*(++n_it4);
return true;
}
}
}
return true;//will never reach here
}
// Non recursive template function
template <class BidIt>
inline bool prev_combination(BidIt n_begin, BidIt n_end,
BidIt r_begin, BidIt r_end)
{
bool boolsame=false;
BidIt marked;//for r
BidIt r_marked;
BidIt n_marked;
BidIt tmp_n_end=n_end;
--tmp_n_end;
BidIt r_it1=r_end;
--r_it1;
for(BidIt n_it1=tmp_n_end; n_it1!=n_begin || n_it1==n_begin ; --n_it1)
{
if(*r_it1==*n_it1)
{
r_marked=r_it1;
n_marked=n_it1;
break;
}
}
BidIt n_it2=n_marked;
BidIt tmp_r_end=r_end;
--tmp_r_end;
for(BidIt r_it2=r_marked; r_it2!=r_begin || r_it2==r_begin; --r_it2,--n_it2)
{
if(*r_it2==*n_it2 )
{
if(r_it2==r_begin&& !(*r_it2==*n_begin) )
{
for(BidIt n_it3=n_begin;n_it3!=n_end;++n_it3)
{
if(*r_it2==*n_it3)
{
marked=r_it2;
*r_it2=*(--n_it3);
BidIt n_it4=n_end;
--n_it4;
for(BidIt r_it3=tmp_r_end; (r_it3!=r_begin || r_it3==r_begin) &&r_it3!=marked; --r_it3,--n_it4)
{
*r_it3=*n_it4;
}
return true;
}
}
}
else if(r_it2==r_begin&&*r_it2==*n_begin)
{
return false;//no more previous combination;
}
}
else //if(*r_it2!=*n_it2 )
{
++r_it2;
marked=r_it2;
for(BidIt n_it5=n_begin;n_it5!=n_end;++n_it5)
{
if(*r_it2==*n_it5)
{
*r_it2=*(--n_it5);
BidIt n_it6=n_end;
--n_it6;
for(BidIt r_it4=tmp_r_end; (r_it4!=r_begin || r_it4==r_begin) &&r_it4!=marked; --r_it4,--n_it6)
{
*r_it4=*n_it6;
}
return true;
}
}
}
}
return false;//Will never reach here, unless error
}
// Non recursive template function with Pred
template <class BidIt, class Prediate>
inline bool prev_combination(
BidIt n_begin,
BidIt n_end,
BidIt r_begin,
BidIt r_end,
Prediate Equal)
{
bool boolsame=false;
BidIt marked;//for r
BidIt r_marked;
BidIt n_marked;
BidIt tmp_n_end=n_end;
--tmp_n_end;
BidIt r_it1=r_end;
--r_it1;
for(BidIt n_it1=tmp_n_end; n_it1!=n_begin || n_it1==n_begin ; --n_it1)
{
if( Equal(*r_it1, *n_it1) )
{
r_marked=r_it1;
n_marked=n_it1;
break;
}
}
BidIt n_it2=n_marked;
BidIt tmp_r_end=r_end;
--tmp_r_end;
for(BidIt r_it2=r_marked; r_it2!=r_begin || r_it2==r_begin; --r_it2,--n_it2)
{
if( Equal(*r_it2, *n_it2) )
{
if(r_it2==r_begin&& !Equal(*r_it2, *n_begin) )
{
for(BidIt n_it3=n_begin;n_it3!=n_end;++n_it3)
{
if(Equal(*r_it2, *n_it3))
{
marked=r_it2;
*r_it2=*(--n_it3);
BidIt n_it4=n_end;
--n_it4;
for(BidIt r_it3=tmp_r_end; (r_it3!=r_begin || r_it3==r_begin) &&r_it3!=marked; --r_it3,--n_it4)
{
*r_it3=*n_it4;
}
return true;
}
}
}
else if(r_it2==r_begin&&Equal(*r_it2, *n_begin))
{
return false;//no more previous combination;
}
}
else //if(*r_it2!=*n_it2 )
{
++r_it2;
marked=r_it2;
for(BidIt n_it5=n_begin;n_it5!=n_end;++n_it5)
{
if(Equal(*r_it2, *n_it5))
{
*r_it2=*(--n_it5);
BidIt n_it6=n_end;
--n_it6;
for(BidIt r_it4=tmp_r_end; (r_it4!=r_begin || r_it4==r_begin) &&r_it4!=marked; --r_it4,--n_it6)
{
*r_it4=*n_it6;
}
return true;
}
}
}
}
return false;//Will never reach here, unless error
}
// Recursive template function
template <class RanIt, class Func>
void recursive_combination(RanIt nbegin, RanIt nend, int n_column,
RanIt rbegin, RanIt rend, int r_column,int loop, Func func)
{
int r_size=rend-rbegin;
int localloop=loop;
int local_n_column=n_column;
//A different combination is out
if(r_column>(r_size-1))
{
func(rbegin,rend);
return;
}
/////////////////////////////////
for(int i=0;i<=loop;++i)
{
RanIt it1=rbegin;
for(int cnt=0;cnt<r_column;++cnt)
{
++it1;
}
RanIt it2=nbegin;
for(int cnt2=0;cnt2<n_column+i;++cnt2)
{
++it2;
}
*it1=*it2;
++local_n_column;
recursive_combination(nbegin,nend,local_n_column,
rbegin,rend,r_column+1,localloop,func);
--localloop;
}
}
}
#endif
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