int main()
{
ifstream f("retea2.in");
ofstream g("retea2.out");
f>>n>>m;
for(int i=1; i<=n; ++i) f>>p[i].x>>p[i].y;
int bi;
for(int i=1;i<=m; ++i) {
f>>p[i+n].x>>p[i+n].y;
dmin[i]=INF;
for(int j=1; j<=n; ++j) dmin[i]=min(dmin[i],dist(p[j],p[i+n]));
if(bd>dmin[i]) {
bd=dmin[i];
bi=i;
}
b.insert(i);
}
for(;b.size();) {
b.erase(b.find(bi));
cst+=bd;
bd=INF;
for(is i=b.begin(); i!=b.end(); ++i) dmin[*i]=min(dmin[*i],dist(p[bi+n],p[*i+n]));
for(is i=b.begin(); i!=b.end(); ++i) if(bd>dmin[*i]) {
bd=dmin[*i];
bi=*i;
}
}
g<<fixed<<setprecision(6)<<cst;
cout<<fixed<<setprecision(6)<<cst;
return 0;
}
void remove_sets_not_containing(const uint x){
if(fix.find(x) == fix.end()){ // if x in fix, then x is already in all sets
if(variable.find(x) != variable.end()){ // if x is optional, then make it madatory
fix.insert(x);
variable.erase(x);
} else clear(); // if x is not in any set, then remove all sets
}
}
// remove all sets that (do not) contain an item
void remove_sets_containing(const uint x){
if(fix.find(x) == fix.end()) // if x not in fix, then just remove all occurances of it from variable
variable.erase(x);
else clear(); // if x in fix, then all sets contain x, so clear the compact_set
}
// check containment of (lists of) items in all/some of the sets
bool all_sets_contain(const uint x) const{
return fix.find(x) != fix.end();
}
bool some_sets_contain(const uint x) const{
return (fix.find(x) != fix.end()) || (variable.find(x) != variable.end());
}
// add or remove a (list of) items from all sets
inline void add_to_all(const uint x){
fix.insert(x);
}
inline void remove_all_from_all(const uint x){
fix.erase(x);
variable.erase(x);
}
// return whether there are some elements that are fix
inline bool has_no_fixed_elements() const {
return fix.empty();
}
// multiply all sets in the list with all subsets of X (add all subsets to all sets in the list)
inline void multiply_with_subsets(const list<uint>& X){
for(uint x: X) variable.insert(x);
}
// multiply all sets in the list with one set X (add this set to all sets in the list)
inline void multiply_with_set(const list<uint>& X){
for(uint x: X) fix.insert(x);
}
// clear
inline void clear(){
fix.clear();
variable.clear();
}
// return whether the list contains no element
bool empty() const{
return fix.empty() && variable.empty();
}
