Submission #639731

#	Time	Username	Problem	Language	Result	Execution time	Memory
639731		KiriLL1ca	Bridges (APIO19_bridges)	C++14	100 / 100	2523 ms	9992 KiB

bridges

#include <iostream>
#include <vector>
#include <array>
#include <algorithm>
#include <numeric>
#define fr first
#define sc second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pw(x) (1ll << x)
#define sz(x) (int)((x).size())
#define pb push_back
#define endl '\n'

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;

template <typename T> inline bool umin (T &a, const T &b) { if (a > b) { a = b; return 1; } return 0; }
template <typename T> inline bool umax (T &a, const T &b) { if (a < b) { a = b; return 1; } return 0; }

const int N = 1e5 + 100;
const int buben = 800;
      
struct dsu {
        vector <int> p, rk;
        vector <array <int, 6>> st;
        dsu () {}
        dsu (int n) : p(n), rk(n, 1), st() { iota(all(p), 0); }
        inline int par (int x) { while (p[x] != x) x = p[x]; return x; }
        inline bool unite (int x, int y) {
                x = par(x), y = par(y);
                if (x == y) return 0;
                if (rk[x] < rk[y]) swap(x, y);
                st.pb({x, y, p[x], p[y], rk[x], rk[y]});
                rk[x] += rk[y]; p[y] = x; return 1;
        }
        inline void rollback () {
                if (!sz(st)) { cout << "ebis"; exit(0); }
                auto [x, y, px, py, rkx, rky] = st.back(); st.pop_back();
                p[x] = px; p[y] = py;
                rk[x] = rkx; rk[y] = rky;
        }
        inline bool same (int x, int y) { return par(x) == par(y); }
        inline int size (int x) { return rk[par(x)]; }
};       

inline void solve () {
        int n, m; cin >> n >> m;
        vector <array <int, 3>> edge (m);
        for (auto &[i, j, k] : edge) cin >> i >> j >> k, --i, --j;
        int q; cin >> q;
        vector <array <int, 3>> qry (q);
        for (auto &[t, i, j] : qry) cin >> t >> i >> j, --i;
        vector <int> ans (q, -1);
        for (int l = 0; l < q; l += buben) {
                int r = min(q, l + buben);
                vector <bool> chg (m);
                vector <array <int, 3>> ask, unchg;
                vector <int> upd;
                
                for (int i = l; i < r; ++i) {
                        if (qry[i][0] == 1) {
                                chg[qry[i][1]] = 1; upd.pb(qry[i][1]);
                        }
                        else {
                                ask.pb({qry[i][2], qry[i][1], i});
                        }
                }
                
                for (int i = 0; i < m; ++i) if (!chg[i]) unchg.pb({edge[i][2], edge[i][0], edge[i][1]});
                vector <vector <array <int, 3>>> add (buben);
                
                for (int i = l; i < r; ++i) {
                        if (qry[i][0] == 1) {
                                edge[qry[i][1]][2] = qry[i][2];
                        }
                        else {
                                for (auto j : upd) if (edge[j][2] >= qry[i][2]) add[i - l].pb(edge[j]);
                        }
                }
                
                sort(rall(ask)); sort(rall(unchg));
                
                int uk = 0;
                dsu D (n);
                for (auto [d, v, id] : ask) {
                        while (uk < sz(unchg) && unchg[uk][0] >= d) {
                                D.unite(unchg[uk][1], unchg[uk][2]);
                                ++uk; 
                        }
                        int cnt = 0;
                        for (auto [u, v, w] : add[id - l]) {
                                cnt += D.unite(u, v); 
                        }
                        ans[id] = D.size(v);
                        while (cnt--) D.rollback();
                }
        }
        for (auto i : ans) if (~i) cout << i << endl;
}

signed main() {
        ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
        int t = 1; // cin >> t;
        while (t--) solve();
        return 0;
}

Compilation message (stderr)

bridges.cpp: In member function 'void dsu::rollback()':
bridges.cpp:43:22: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   43 |                 auto [x, y, px, py, rkx, rky] = st.back(); st.pop_back();
      |                      ^
bridges.cpp: In function 'void solve()':
bridges.cpp:54:20: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   54 |         for (auto &[i, j, k] : edge) cin >> i >> j >> k, --i, --j;
      |                    ^
bridges.cpp:57:20: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   57 |         for (auto &[t, i, j] : qry) cin >> t >> i >> j, --i;
      |                    ^
bridges.cpp:90:27: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   90 |                 for (auto [d, v, id] : ask) {
      |                           ^
bridges.cpp:96:35: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   96 |                         for (auto [u, v, w] : add[id - l]) {
      |                                   ^

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 14 / 14
• Subtask 5: 13 / 13
• Subtask 6: 27 / 27