# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
938070 | mat_jur | Bridges (APIO19_bridges) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
auto&operator<<(auto &o, pair<auto, auto> p) {o << "(" << p.first << ", " << p.second << ")"; return o;}
auto operator<<(auto &o, auto x)->decltype(x.end(), o) {o<<"{"; for(auto e : x) o<<e<<", "; return o<<"}";}
#define debug(X) cerr << "["#X"]: " << X << '\n';
#else
#define cerr if(0)cout
#define debug(X) ;
#endif
#define ll long long
#define all(v) (v).begin(), (v).end()
#define ssize(x) int(x.size())
#define fi first
#define se second
#define mp make_pair
#define eb emplace_back
struct dynamicUF {
vector<int> e;
dynamicUF(int n): e(n, -1) {}
stack<array<int, 3>> s;
int get(int a) {return e[a] < 0 ? a : get(e[a]);}
int unionn(int a, int b) {
a = get(a); b = get(b);
if(a == b) return 0;
if(-e[a] > -e[b]) swap(a, b);
s.push({a, b, e[a]});
e[b] += e[a];
e[a] = b;
return 1;
}
void roll_back(int m = 1) {
while (m--) {
auto [a, b, sz] = s.top();
s.pop();
e[b] -= sz;
e[a] = sz;
}
}
};
int main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
int n, m;
cin >> n >> m;
vector<int> w[2], u(m), v(m);
w[0] = vector(m, 0);
for(int i = 0; i < m; ++i) {
cin >> u[i] >> v[i] >> w[0][i];
u[i]--; v[i]--;
}
int q;
cin >> q;
vector<int> ans(q, -1);
const int B = 600;
vector<pair<int, int>> ev;
vector<bool> changed(m);
vector<array<int, 3>> upd;
vector<int> s(q);
vector<int> C(q);
auto clean = [&](int L, int R) {
for(int i = L; i <= R; i++)
if(C[i] == 1) changed[s[i]] = true;
else ev.eb(mp(i, 1));
dynamicUF sp(n);
for(int i = 0; i < m; ++i) {
if(!changed[i]) ev.eb(mp(i, 0));
else changed[i] = false;
}
sort(all(ev), [&](pair<int, int> x, pair<int, int> y) {
if (w[x.se][x.fi] != w[y.se][y.fi]) return w[x.se][x.fi] > w[y.se][y.fi];
return x.se < y.se;
});
for(auto [idx, c] : ev) {
if(c == 0) {
sp.unionn(u[idx], v[idx]);
}
else {
int d = w[1][idx], a = s[idx], b = idx;
map<int, int> M;
for(int t = L; t <= R; ++t) {
if(C[t] != 1) continue;
if(t <= b) M[s[t]] = w[1][t];
else if(M[s[t]] == 0) M[s[t]] = w[0][s[t]];
}
int cnt = 0;
for(auto [idx2, r] : M) {
if(r >= d) cnt += sp.unionn(u[idx2], v[idx2]);
}
ans[b] = -sp.e[sp.get(a)];
sp.roll_back(cnt);
}
}
for(auto [idx, r, t] : upd) {
w[0][idx] = r;
}
upd.clear();
ev.clear();
};
w[1] = vector(q, 0);
for(int t = 0; t < q; ++t) {
cin >> C[t];
cin >> s[t] >> w[1][t];
s[t]--;
// if(c == 1) {
// int b, r;
// cin >> b >> r;
// b--;
// changed[b] = true;
// upd.eb((array<int, 3>){b, r, t});
// }
// else {
// s[t]--;
// ev.eb(mp(t, 1));
// }
}
for(int i = 0; i < q; i += B) {
clean(i, min(q-1, i+B-1));
}
for(int i = 0; i < q; i++) if(ans[i] > -1) cout << ans[i] << '\n';
return 0;
}