#include <bits/stdc++.h>
using namespace std;
#define pii pair<long long,int>
const int N = 1e5 + 1;
const int K = 6;
int n,m,k;
vector<pair<int,int> > adj[N];
vector<int> imp;
int idx[N];
bool visited[N],used[N][N];
long long dist[K][N],dis1[N],dis2[N],ans = LLONG_MAX;
priority_queue<pii,vector<pii>,greater<pii> > q;
void dijk(int x,long long (&dist)[N])
{
for(int i = 1;i <= n;i++) visited[i] = false,dist[i] = LLONG_MAX;
dist[x] = 0;
q.push({0,x});
while(!q.empty())
{
int u = q.top().second;
q.pop();
if(visited[u]) continue;
visited[u] = true;
for(auto [w,v] : adj[u]) if(dist[u]+w<dist[v]) dist[v] = dist[u]+w,q.push({dist[v],v});
}
}
long long cal(int a,int b)
{
if(idx[a]) return dist[idx[a]][b];
else return dist[idx[b]][a];
}
void solve2(){ ans = min(ans,cal(imp[0],imp[1])); }
void solve3()
{
for(int i = 1;i <= n;i++)
{
long long each = 0;
for(int x : imp) each+=cal(i,x);
ans = min(ans,each);
}
}
void dijktwo()
{
for(int i = 1;i <= n;i++) q.push({dis1[i],i}),visited[i] = false;
while(!q.empty())
{
int u = q.top().second;
q.pop();
if(visited[u]) continue;
visited[u] = true;
ans = min(ans,dis1[u]+dis2[u]);
for(auto [w,v] : adj[u]) if(dis1[u]+w<dis1[v]) dis1[v] = dis1[u]+w,q.push({dis1[v],v});
}
}
void solve4()
{
long long each = 0;
for(int i = 0;i < k-1;i++) each+=cal(imp[i],imp[i+1]);
ans = min(ans,each);
for(int i = 1;i <= n;i++) ans = min(ans,cal(imp[0],imp[1])+cal(imp[1],i)+cal(imp[2],i)+cal(imp[3],i));
for(int i = 1;i <= n;i++) dis1[i] = cal(imp[0],i)+cal(imp[1],i),dis2[i] = cal(imp[2],i)+cal(imp[3],i);
dijktwo();
}
void solve5s()
{
for(int i = 1;i <= n;i++) dis1[i] = cal(imp[0],i)+cal(imp[1],i),dis2[i] = cal(imp[2],i)+cal(imp[3],i)+cal(imp[4],i);
dijktwo();
for(int i = 1;i <= n;i++) dis1[i] = cal(imp[0],i)+cal(imp[1],i),dis2[i] = cal(imp[2],imp[3])+cal(imp[3],i)+cal(imp[4],i);
dijktwo();
}
void solve5()
{
long long each = 0;
for(int i = 0;i < k-1;i++) each+=cal(imp[i],imp[i+1]);
ans = min(ans,each);
ans = min(ans,cal(imp[0],imp[1])+cal(imp[0],imp[2])+cal(imp[0],imp[3])+cal(imp[3],imp[4]));
for(int i = 1;i <= n;i++)
{
ans = min(ans,cal(imp[0],i)+cal(imp[1],i)+cal(imp[2],i)+cal(imp[3],i)+cal(imp[3],imp[4]));
ans = min(ans,cal(imp[0],imp[1])+cal(imp[1],i)+cal(imp[2],i)+cal(imp[3],i)+cal(imp[4],imp[3]));
ans = min(ans,cal(imp[0],imp[1])+cal(imp[1],imp[2])+cal(imp[2],i)+cal(imp[3],i)+cal(imp[4],i));
ans = min(ans,cal(imp[0],imp[2])+cal(imp[2],imp[1])+cal(imp[2],i)+cal(i,imp[3])+cal(imp[4],imp[3]));
ans = min(ans,cal(imp[0],i)+cal(imp[1],i)+cal(imp[2],i)+cal(imp[3],imp[2])+cal(imp[4],imp[2]));
ans = min(ans,cal(imp[0],i)+cal(imp[1],i)+cal(imp[2],imp[1])+cal(imp[3],imp[1])+cal(imp[4],imp[3]));
}
if(imp[0]<imp[1] and !used[idx[imp[0]]][idx[imp[1]]]) used[idx[imp[0]]][idx[imp[1]]] = true,solve5s();
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n >> k >> m;
for(int i = 1;i <= k;i++)
{
int x;
cin >> x;
imp.push_back(x);
idx[x] = i;
}
for(int i = 0;i < m;i++)
{
int a,b,d;
cin >> a >> b >> d;
adj[a].push_back({d,b});
adj[b].push_back({d,a});
}
for(int x : imp) dijk(x,dist[idx[x]]);
sort(imp.begin(),imp.end());
do
{
if(k==2) solve2();
else if(k==3) solve3();
else if(k==4) solve4(),solve3();
else solve5(),solve3();
}while(next_permutation(imp.begin(),imp.end()));
cout << ans;
}
Compilation message
cities.cpp: In function 'void dijk(int, long long int (&)[100001])':
cities.cpp:27:18: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
for(auto [w,v] : adj[u]) if(dist[u]+w<dist[v]) dist[v] = dist[u]+w,q.push({dist[v],v});
^
cities.cpp: In function 'void dijktwo()':
cities.cpp:59:18: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
for(auto [w,v] : adj[u]) if(dis1[u]+w<dis1[v]) dis1[v] = dis1[u]+w,q.push({dis1[v],v});
^
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::(anonymous namespace)::__destroy_string<wchar_t>(void*)':
(.text._ZNSt13__facet_shims12_GLOBAL__N_116__destroy_stringIwEEvPv+0x1e): relocation truncated to fit: R_X86_64_32S against symbol `std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::_Rep::_S_empty_rep_storage' defined in .bss._ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE[_ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-wstring-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::(anonymous namespace)::__destroy_string<char>(void*)':
(.text._ZNSt13__facet_shims12_GLOBAL__N_116__destroy_stringIcEEvPv+0x1e): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `std::__facet_shims::(anonymous namespace)::money_get_shim<wchar_t>::do_get(std::istreambuf_iterator<wchar_t, std::char_traits<wchar_t> >, std::istreambuf_iterator<wchar_t, std::char_traits<wchar_t> >, bool, std::ios_base&, std::_Ios_Iostate&, std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >&) const':
(.text._ZNKSt13__facet_shims12_GLOBAL__N_114money_get_shimIwE6do_getESt19istreambuf_iteratorIwSt11char_traitsIwEES6_bRSt8ios_baseRSt12_Ios_IostateRSbIwS5_SaIwEE+0xfe): relocation truncated to fit: R_X86_64_32S against symbol `std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::_Rep::_S_empty_rep_storage' defined in .bss._ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE[_ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-wstring-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `std::__facet_shims::(anonymous namespace)::money_get_shim<wchar_t>::do_get(std::istreambuf_iterator<wchar_t, std::char_traits<wchar_t> >, std::istreambuf_iterator<wchar_t, std::char_traits<wchar_t> >, bool, std::ios_base&, std::_Ios_Iostate&, std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >&) const':
(.text._ZNKSt13__facet_shims12_GLOBAL__N_114money_get_shimIwE6do_getESt19istreambuf_iteratorIwSt11char_traitsIwEES6_bRSt8ios_baseRSt12_Ios_IostateRSbIwS5_SaIwEE+0x17b): relocation truncated to fit: R_X86_64_32S against symbol `std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::_Rep::_S_empty_rep_storage' defined in .bss._ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE[_ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-wstring-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `std::__facet_shims::(anonymous namespace)::money_get_shim<char>::do_get(std::istreambuf_iterator<char, std::char_traits<char> >, std::istreambuf_iterator<char, std::char_traits<char> >, bool, std::ios_base&, std::_Ios_Iostate&, std::string&) const':
(.text._ZNKSt13__facet_shims12_GLOBAL__N_114money_get_shimIcE6do_getESt19istreambuf_iteratorIcSt11char_traitsIcEES6_bRSt8ios_baseRSt12_Ios_IostateRSs+0xfe): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `std::__facet_shims::(anonymous namespace)::money_get_shim<char>::do_get(std::istreambuf_iterator<char, std::char_traits<char> >, std::istreambuf_iterator<char, std::char_traits<char> >, bool, std::ios_base&, std::_Ios_Iostate&, std::string&) const':
(.text._ZNKSt13__facet_shims12_GLOBAL__N_114money_get_shimIcE6do_getESt19istreambuf_iteratorIcSt11char_traitsIcEES6_bRSt8ios_baseRSt12_Ios_IostateRSs+0x17b): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::__numpunct_fill_cache<char>(std::integral_constant<bool, false>, std::locale::facet const*, std::__numpunct_cache<char>*)':
(.text._ZNSt13__facet_shims21__numpunct_fill_cacheIcEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E[_ZNSt13__facet_shims21__numpunct_fill_cacheIcEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E]+0xa1): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::__numpunct_fill_cache<char>(std::integral_constant<bool, false>, std::locale::facet const*, std::__numpunct_cache<char>*)':
(.text._ZNSt13__facet_shims21__numpunct_fill_cacheIcEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E[_ZNSt13__facet_shims21__numpunct_fill_cacheIcEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E]+0x24f): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::__numpunct_fill_cache<wchar_t>(std::integral_constant<bool, false>, std::locale::facet const*, std::__numpunct_cache<wchar_t>*)':
(.text._ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E[_ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E]+0xa9): relocation truncated to fit: R_X86_64_32S against symbol `std::string::_Rep::_S_empty_rep_storage' defined in .bss._ZNSs4_Rep20_S_empty_rep_storageE[_ZNSs4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-string-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::__numpunct_fill_cache<wchar_t>(std::integral_constant<bool, false>, std::locale::facet const*, std::__numpunct_cache<wchar_t>*)':
(.text._ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E[_ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E]+0x114): relocation truncated to fit: R_X86_64_32S against symbol `std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::_Rep::_S_empty_rep_storage' defined in .bss._ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE[_ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE] section in /usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-wstring-inst.o)
/usr/lib/gcc/x86_64-linux-gnu/7/libstdc++.a(cow-shim_facets.o): In function `void std::__facet_shims::__numpunct_fill_cache<wchar_t>(std::integral_constant<bool, false>, std::locale::facet const*, std::__numpunct_cache<wchar_t>*)':
(.text._ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E[_ZNSt13__facet_shims21__numpunct_fill_cacheIwEEvSt17integral_constantIbLb0EEPKNSt6locale5facetEPSt16__numpunct_cacheIT_E]+0x294): additional relocation overflows omitted from the output
collect2: error: ld returned 1 exit status
