Submission #632834

#	Time	Username	Problem	Language	Result	Execution time	Memory
632834		erto	Bridges (APIO19_bridges)	C++17	59 / 100	3085 ms	118636 KiB

bridges

#include <bits/stdc++.h>
typedef long long int ll;
#define INF 1000000007
#define INF2 998244353
#define N (ll)(1e5+ 5)
using namespace std;
//#define int ll
#define lsb(x) (x & (-x))
 
const int K = 320;
int n, m,  cur=0, g, h, q;
int u[N], v[N], d[N];
int x[N], y[N], ans[N];
bool used[N];
pair<int, int> upd[N], qu[N];
vector<int> lis[N];

int p[N], sz[N];
vector<int> tb;

int get(int x){
    while(x != p[x])x = p[x];
    return x;
}

void unite(int x, int y){
    int a = get(x), b = get(y);
    if(a == b)return;
    if(sz[a] < sz[b]){
        swap(a, b);
    }
    p[b] = a;
    sz[a] += sz[b];
    tb.push_back(b);
}

void revert(int x){
    while(tb.size() > x){
        int t = tb.back();
        sz[p[t]] -= sz[t];
        p[t] = t;
        tb.pop_back();
    }
}

bool c1(int x, int y){
    return d[x] > d[y];
}

bool c2(int x, int y){
    return qu[x].second > qu[y].second;
}

void solve(){
    cin >> n >> m;
    for(int i=1; i<=m; i++){
        cin >> u[i] >> v[i] >> d[i];
    }

    cin >> q;
    for(int i=1; i<=q; i++){
        cin >> g;
        if(g == 1){
            cin >> g >> h;
            upd[i] = {g, h};
        }
        else{
            cin >> g >> h;
            qu[i] = {g, h};
        }
    }

    for(int i=0; i<= q / K; i++){
        int l = max(1, i * K), r = min((i + 1) * K, q + 1);
        memset(used, 0, m + 1);
        fill(sz + 1, sz + n + 1, 1);
        iota(p + 1, p + n + 1, 1);

        vector<int> ch, ask, uch;
        for(int j=l; j<r; j++){
            if(upd[j].first){
                used[upd[j].first] = 1;
                ch.push_back(j);
            }
            else{
                ask.push_back(j);
            }
        }

        for(int j=l; j<r; j++){
            if(qu[j].first){
                for(int u : ch){
                    if(d[upd[u].first] >= qu[j].second){
                      lis[j].push_back(upd[u].first);
                    }
                }
            }
            else{
                d[upd[j].first] = upd[j].second;
            }
        }

        for(int j=1; j<=m; j++){
            if(!used[j])uch.push_back(j);
        }
        sort(uch.begin(), uch.end(), c1);
        sort(ask.begin(), ask.end(), c2);

        int p1 = 0;
        for(int j : ask){
            while(p1 < uch.size() && qu[j].second <= d[uch[p1]]){
                unite(u[uch[p1]], v[uch[p1]]);
                p1++;
            }
            int prev = tb.size();
            for(int l : lis[j]){
                unite(u[l], v[l]);
            }
            ans[j] = sz[get(qu[j].first)];
            revert(prev);
        }
    }
    for(int i=1; i<=q; i++){
        if(qu[i].first)cout << ans[i] << '\n';
    }
}
 
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    //cin>>T;
    while (T--){
        solve();
    }
}

Compilation message (stderr)

bridges.cpp: In function 'void revert(int)':
bridges.cpp:38:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   38 |     while(tb.size() > x){
      |           ~~~~~~~~~~^~~
bridges.cpp: In function 'void solve()':
bridges.cpp:111:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  111 |             while(p1 < uch.size() && qu[j].second <= d[uch[p1]]){
      |                   ~~~^~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 0 / 14
• Subtask 5: 13 / 13
• Subtask 6: 0 / 27