Created
April 5, 2010 17:30
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#include <iostream> | |
#include <bitset> | |
#include <vector> | |
#include <algorithm> | |
#include <cstdio> | |
#include <cstdlib> | |
using namespace std; | |
const int N=1000; | |
int counter=0; | |
int ub; | |
class bitarray{ | |
public: | |
int id; | |
bitset<N> * b; | |
bitarray(int i){ | |
id = i; | |
b = new bitset<N>; | |
} | |
bitarray(const bitarray& c){ | |
id = c.id; | |
b = new bitset<N>; | |
if(b==NULL){ | |
cout<< "DEATH"; | |
exit(1); | |
} | |
(*b)|= (*(c.b)); | |
} | |
int size(){ | |
return (*b).count(); | |
} | |
void print(){ | |
for(int i=0;i<((*b).size());i++){ | |
cout << ((*b)[i]); | |
} | |
cout << "\n"; | |
} | |
void removeAll(const bitarray& a){ | |
*b &= ~(*(a.b)); | |
} | |
void add(int i){ | |
(*b).set(i); | |
} | |
int contains(int i){ | |
return (*b)[i]; | |
} | |
int containsAll(const bitarray& a){ | |
if((*b|*(a.b)) == *b){ | |
return 1; | |
} | |
return 0; | |
} | |
}; | |
void remove_set(bitarray& universe, vector<bitarray>& sets, int pick){ | |
bitarray r (sets[pick]); | |
sets.erase(sets.begin()+pick); | |
universe.removeAll(r); | |
for(int i=0;i<sets.size();i++){ | |
sets[i].removeAll(r); | |
} | |
} | |
void remove_subsets(vector<bitarray>& sets){ | |
for(int i=0;i<sets.size();i++){ | |
for(int j=i+1;j<sets.size();j++){ | |
while(j<sets.size() && sets[i].containsAll(sets[j])){ | |
sets.erase(sets.begin()+j); | |
} | |
} | |
} | |
} | |
vector<bitarray> deep_clone(const vector<bitarray>& sets){ | |
vector<bitarray> v; | |
for(int i=0;i<sets.size();i++){ | |
bitarray p (sets[i]); | |
v.push_back(p); | |
} | |
return v; | |
} | |
int set_sorter(const bitarray& a, const bitarray& c){ | |
if(((*(a.b)).count())<((*(c.b)).count())){ | |
return 0; | |
} | |
return 1; | |
} | |
int branch_value(bitarray& universe, vector<bitarray>& sets){ | |
for(int i=0;i<(*(universe.b)).size();i++){ | |
if(universe.contains(i)){ | |
int c = 0; | |
int t = 0; | |
for(int j =0;j<sets.size();j++){ | |
if(sets[j].contains(i)){ | |
t=j; | |
c++; | |
if(c==2){ | |
break; | |
} | |
} | |
} | |
if(c==0){ | |
return -2; | |
} | |
if(c==1){ | |
return t; | |
} | |
} | |
} | |
return -1; | |
} | |
void bb(bitarray& universe, vector<bitarray>& sets, vector<int>& chosen){ | |
counter++; | |
if(chosen.size()>=ub){ | |
return; | |
} | |
if((*(universe.b)).none()){ | |
ub = chosen.size(); | |
return; | |
} | |
if(chosen.size()==ub-2){ | |
for(int i=0;i<sets.size();i++){ | |
if(sets[i].size() == universe.size()){ | |
chosen.push_back(sets[i].id); | |
ub = chosen.size(); | |
chosen.pop_back(); | |
return; | |
} | |
} | |
} | |
sort(sets.begin(),sets.end(),set_sorter); | |
remove_subsets(sets); | |
int sum = 0; | |
for(int i=0;i<ub-chosen.size()&&i<sets.size();i++){ | |
sum+= sets[i].size(); | |
} | |
if(sum<universe.size()){ | |
return; | |
} | |
int bv = branch_value(universe,sets); | |
if(bv==-2){ | |
return; | |
} | |
bitarray nu (universe); | |
vector<bitarray> ns = deep_clone(sets); | |
if(bv!=-1){ | |
chosen.push_back(sets[bv].id); | |
remove_set(nu,ns,bv); | |
bb(nu,ns,chosen); | |
chosen.pop_back(); | |
}else{ | |
chosen.push_back(sets[0].id); | |
remove_set(nu,ns,0); | |
bb(nu,ns,chosen); | |
chosen.pop_back(); | |
sets.erase(sets.begin()); | |
bb(universe,sets,chosen); | |
} | |
} | |
int main (){ | |
int e; | |
int n; | |
scanf("%d",&e); | |
scanf("%d",&n); | |
vector<bitarray> s; | |
for(int i=0;i<n;i++){ | |
int x; | |
scanf("%d",&x); | |
bitarray p (i); | |
for(int j=0;j<x;j++){ | |
int t; | |
scanf("%d",&t); | |
(*(p.b)).set(t); | |
} | |
s.push_back(p); | |
} | |
bitarray universe (0); | |
for(int i=0;i<n;i++){ | |
(*(universe.b))|=(*(s[i].b)); | |
} | |
vector<int> chosen; | |
ub = s.size(); | |
bb(universe,s,chosen); | |
cout<<ub; | |
cout<<endl; | |
cout<<counter; | |
cout<<endl; | |
return 0; | |
} |
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