#include<bits/stdc++.h>
#include<fstream>
using namespace std;
#define sz(a) (int)a.size()
#define ALL(v) v.begin(), v.end()
#define ALLR(v) v.rbegin(), v.rend()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mpp make_pair
const ld PI = 3.14159265359, prec = 1e-9;;
//using u128 = __uint128_t;
//const int x[4] = {1, 0, -1, 0};
//const int y[4] = {0, -1, 0, 1};
const ll mod =1e9 + 7, pr = 31;
const int mxn = 5e5 + 5, mxq = 1e5 + 5, sq = 500, mxv = 5e4 + 1;
//const int base = (1 <<18);
const ll inf = 1e13 + 5, neg = -69420, inf2 = 1e14;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// have fun!
struct E{
ll u, v, w;
bool operator <(const E &other){
return(w < other.w);
}
};
struct EV{
int node, pre, curr;
};
ll n, a, b, k;
ll c2(ll n){
return(n * (n - 1) / 2);
}
struct DSU{
ll tot = 0;
ll pa[mxn + 1], siz[mxn + 1];
vt<int>node[mxn + 1];
int fp(int u){
if(pa[u] == u)return(u);
return(pa[u] = fp(pa[u]));
}
void init(){
for(int i = 1; i <= n; i++){
pa[i] = i; siz[i] = 1; node[i].clear(); node[i].pb(i);
}
tot = 0;
}
vt<EV>unon(int u, int v){
u = fp(u); v = fp(v);
vt<EV>events;
if(u == v)return(events);
tot += siz[u] * siz[v];
if(siz[u] < siz[v])swap(u, v);
siz[u] += siz[v]; pa[v] = u;
for(auto i: node[v]){
node[u].pb(i); events.pb({i, v, u});
}
return(events);
}
};
DSU dsu;
vt<E>edgea, edgeb;
vt<EV>eva[mxn + 1], evb[mxn + 1];
ll canda[mxn + 1], candb[mxn + 1];
int paa[mxn + 1], pab[mxn + 1];
map<pair<int, int>, ll>mp;
void solve(){
cin >> n >> a >> b >> k;
if(k == 0){
cout << 0; return;
}
for(int i = 0; i < a; i++){
int u, v, w; cin >> u >> v >> w;
edgea.pb({u, v, w});
}
for(int i = 0; i < b; i++){
int u, v, w; cin >> u >> v >> w;
edgeb.pb({u, v, w});
}
sort(ALL(edgea)); sort(ALL(edgeb));
dsu.init();
ll ans = inf;
for(int i = 0; i < sz(edgea); i++){
eva[i + 1] = dsu.unon(edgea[i].u, edgea[i].v);
canda[i + 1] = dsu.tot;
if(dsu.tot >= k)ans = min(ans, edgea[i].w);
}
dsu.init();
for(int i = 0; i < sz(edgeb); i++){
evb[i + 1] = dsu.unon(edgeb[i].u, edgeb[i].v);
candb[i + 1] = dsu.tot;
if(dsu.tot >= k)ans = min(ans, edgeb[i].w);
}
for(int i = 1; i <= n; i++){
paa[i] = i; pab[i] = dsu.fp(i);
mp[mpp(paa[i], pab[i])]++;
}
int rp = b;
ll sme = 0; // belonging to both sets
for(int i = 1; i <= a; i++){
for(auto [node, pre, curr]: eva[i]){
//cout << node << " " << pre << " " << curr << "\n";
mp[mpp(paa[node], pab[node])]--;
sme -= mp[mpp(paa[node], pab[node])];
//assert(paa[node] == pre);
paa[node] = curr;
sme += mp[mpp(paa[node], pab[node])];
mp[mpp(paa[node], pab[node])]++;
}
while(canda[i] + candb[rp] - sme >= k && rp >= 1){
for(auto [node, pre, curr]: evb[rp]){
mp[mpp(paa[node], pab[node])]--;
sme -= mp[mpp(paa[node], pab[node])];
//assert(pab[node] == curr);
pab[node] = pre;
sme += mp[mpp(paa[node], pab[node])];
mp[mpp(paa[node], pab[node])]++;
}
rp--;
}
if(rp != b){
cout<<i<<" "<<rp<<" "<<sme<<'\n';
ans = min(ans, edgea[i - 1].w + edgeb[rp].w);
}
}
cout << ((ans == inf) ? -1 : ans);
}
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//freopen("THREE.inp", "r", stdin);
//freopen("THREE.out", "w", stdout);
int tt; tt = 1;
while(tt--){
solve();
}
return(0);
}
Compilation message
Main.cpp: In function 'void solve()':
Main.cpp:112:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
112 | for(auto [node, pre, curr]: eva[i]){
| ^
Main.cpp:122:22: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
122 | for(auto [node, pre, curr]: evb[rp]){
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
16 ms |
35672 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
587 ms |
98772 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
14 ms |
35672 KB |
Output is correct |
| 2 |
Correct |
13 ms |
35568 KB |
Output is correct |
| 3 |
Incorrect |
62 ms |
44600 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
16 ms |
35672 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
