oj.uz

Submission #770928

# Submission time Handle Problem Language Result Execution time Memory
770928 2023-07-02T07:06:12 Z PurpleCrayon Making Friends on Joitter is Fun (JOI20_joitter2) C++17
0 / 100
 5 ms 9684 KB 
#include <bits/stdc++.h>
using namespace std;

#define sz(v) int(v.size())
#define ar array
typedef long long ll;
const int N = 1e5+10, MOD = 1e9+7;

int n, m, par[N];
vector<int> st[N];
set<ar<int, 2>> ed;
set<int> in[N];
vector<ar<int, 2>> use[N];

void solve() {
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        st[i].push_back(i);
        par[i] = i;
    }

    ll ans = 0;

    auto f = [&](int x) {
        assert(x == par[x]);
        return (long long) sz(st[x]) * sz(in[x]);
    };

    auto g = [&](int x) {
        assert(x == par[x]);
        return (long long) sz(st[x]) * (sz(st[x]) - 1);
    };

    auto merge = [&](int a, int b) {
        a = par[a], b = par[b];
        if (a == b) return;
        if (sz(st[a]) < sz(st[b])) swap(a, b);

        vector<ar<int, 2>> change;

        ans -= g(a), ans -= g(b);
        ans -= f(a), ans -= f(b);
        for (int x : st[b]) {
            par[x] = a;
            st[a].push_back(x);
            in[a].erase(x);

            for (auto e : use[x]) {
                change.push_back({e[0], e[1]});
            }
            use[x].clear();
        }

        st[b].clear();

        for (int x : in[b]) {
            if (par[x] != a) {
                in[a].insert(x);
            }
        }
        in[b].clear();

        for (auto e : change) {
            ar<int, 2> ne{par[e[0]], par[e[1]]};
            ed.insert(ne);
            use[ne[0]].push_back(ne);
            use[ne[1]].push_back(ne);
        }

        ans += f(a);
        ans += g(a);
    };

    for (int i = 0; i < m; i++) {
        int a, b; cin >> a >> b, --a, --b;

        ans -= f(par[b]);
        if (par[a] != par[b]) in[par[b]].insert(a);
        ans += f(par[b]);

        ed.insert({par[a], par[b]});
        use[par[a]].push_back({par[a], par[b]});
        use[par[b]].push_back({par[a], par[b]});
        if (ed.count({par[b], par[a]})) {
            merge(a, b);
        }

        cout << ans << '\n';
    }
}

int main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int T = 1;
    // cin >> T;
    while (T--) solve();
}

Subtask #1
0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 4 ms 9684 KB Output is correct
3 Incorrect 4 ms 9684 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 4 ms 9684 KB Output is correct
3 Incorrect 4 ms 9684 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 83.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 4 ms 9684 KB Output is correct
3 Incorrect 4 ms 9684 KB Output isn't correct
4 Halted 0 ms 0 KB -