| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 211494 |
2020-03-20T14:43:15 Z |
VEGAnn |
Bridges (APIO19_bridges) |
C++14 |
|
1061 ms |
12732 KB |
#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define FORd(i, a, b) for (int i = (a) - 1; i >= (b); --i)
#define sz(a) int((a).size())
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
typedef unsigned long long ull;
inline ull isqrt(ull k) {ull r = sqrt(k) + 1; while (r * r > k) r--; return r;}
const int INF = (int) 1e9 + 23111992;
void sol() {
int n_lim = 5e4, m_lim = 1e5, q_lim = 2e5;
int t, n, m; cin >> n >> m;
assert(1 <= n && n <= n_lim);
assert(0 <= m && m <= m_lim);
vector<tuple<int, int, int>> edges;
FOR(i, 0, m) {
int u, v, w; cin >> u >> v >> w; u--, v--, w = -w;
assert(0 <= u && u < n);
assert(0 <= v && v < n);
assert(0 <= -w && -w <= 1e9);
edges.pb(make_tuple(u, v, w));
}
vector<tuple<int, int, int>> queries;
vector<tuple<int, int, int, int>> events;
vi lst_t(m, 0);
int q; cin >> q;
if (n == 1) {
for (int i = 0; i < q; ++i) {
int t, a, b;
cin >> t >> a >> b;
if (t == 2) {
cout << "1\n";
}
}
return;
}
assert(1 <= q && q <= q_lim);
FOR(i, 0, q) {
int op, u, w; cin >> op >> u >> w, u--, w = -w;
assert(1 <= op && op <= 2);
assert(0 <= -w && -w <= 1e9);
if (op == 1) {
events.pb(make_tuple(-get<2>(edges[u]), lst_t[u], i - 1, u));
lst_t[u] = i;
get<2>(edges[u]) = w;
assert(0 <= u && u < m);
}
else {
queries.pb(make_tuple(w, u, i));
assert(0 <= u && u < n);
}
}
FOR(i, 0, m) {
events.pb(make_tuple(-get<2>(edges[i]), lst_t[i], q - 1, i));
}
reverse(all(queries)), sort(all(events));
vii res;
vi adj(m << 1), nxt(m << 1), lst(n, -1);
vi dj(n), size(n);
vi qs(n), vis(n, -1);
int magic = 3 * isqrt(n + m);
for (int lo = 0; lo < q; lo += magic) {
int hi = min(lo + magic - 1, q - 1);
vector<tuple<int, int, int>> queries_t;
while (sz(queries) && get<2>(queries.back()) <= hi) {
queries_t.pb(queries.back());
queries.pop_back();
}
sort(all(queries_t)), reverse(all(queries_t));
FOR(i, 0, n) dj[i] = i, size[i] = 1;
auto find = [&] (int u) {
while (dj[u] ^ u) {
dj[u] = dj[dj[u]];
u = dj[u];
}
return u;
};
auto join = [&] (int u, int v) {
u = find(u), v = find(v);
if (u ^ v) {
if (size[v] < size[u]) {
swap(u, v);
}
dj[u] = v, size[v] += size[u];
}
};
vi use(m);
vector<tuple<int, int, int, int>> events_t, events_o;
for (auto e : events) {
int w, l, r, ix;
tie(w, l, r, ix) = e;
if (!(r < lo) && !(hi < l) && !(l <= lo && hi <= r)) {
events_t.pb(e);
}
if (!use[ix] && !(r < lo) && !(hi < l)) {
use[ix] = 1;
events_o.pb(e);
}
}
reverse(all(events_o));
events_o.pb(make_tuple(-INF, +INF, -INF, 0));
for (auto e : events_o) {
int w, l, r, ix;
tie(w, l, r, ix) = e, w = -w;
while (sz(queries_t) && get<0>(queries_t.back()) < w) {
int wt = get<0>(queries_t.back());
int u = find(get<1>(queries_t.back()));
int t = get<2>(queries_t.back());
int ne = 0;
for (auto ee : events_t) {
int w, l, r, ix;
tie(w, l, r, ix) = ee, w = -w;
if (l <= t && t <= r && w <= wt) {
int u = find(get<0>(edges[ix]));
int v = find(get<1>(edges[ix]));
auto addedge = [&] (int u, int v) {
adj[ne] = v, nxt[ne] = lst[u], lst[u] = ne++;
};
if (u ^ v) {
addedge(u, v), addedge(v, u);
}
}
}
int qh = 0, qe = 0;
vis[u] = t, qs[qe++] = u;
int total = 0;
while (qh < qe) {
int u = qs[qh++];
total += size[u];
for (int ee = lst[u]; ~ee; ee = nxt[ee]) {
int v = adj[ee];
if (vis[v] ^ t) {
vis[v] = t, qs[qe++] = v;
}
}
}
res.pb(mp(t, total));
for (int i = 0; i < ne; i++) {
int u = adj[i];
lst[u] = -1;
}
queries_t.pop_back();
}
int u = get<0>(edges[ix]);
int v = get<1>(edges[ix]);
join(u, v);
}
}
sort(all(res));
FOR(i, 0, sz(res)) cout << res[i].se << "\n";
}
int main(int argc, char* argv[]) {
ios_base::sync_with_stdio(0), cin.tie(0);
if (argc > 1) {
assert(freopen(argv[1], "r", stdin));
cerr << "Generating output for: " << argv[1] << "\n";
}
if (argc > 2) {
assert(freopen(argv[2], "wb", stdout));
}
sol();
cerr << "Time elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n\n";
return 0;
}
Compilation message
bridges.cpp: In function 'void sol()':
bridges.cpp:21:9: warning: unused variable 't' [-Wunused-variable]
int t, n, m; cin >> n >> m;
^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1061 ms |
10572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
883 ms |
6032 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
664 ms |
12732 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1061 ms |
10572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
