Submission #1006280

#	Time	Username	Problem	Language	Result	Execution time	Memory
1006280		c2zi6	Making Friends on Joitter is Fun (JOI20_joitter2)	C++14	0 / 100	1 ms	456 KiB

joitter2

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

VI par;
VI cnt;
vector<set<int>> ing;
int get(int u) {
    return u == par[u] ? u : (par[u] = get(par[u]));
}
void join(int u, int v) {
    u = get(u);
    v = get(v);
    if (u == v) return;
    if (cnt[v] < cnt[u]) swap(u, v);
    cnt[u] += cnt[v];
    for (int x : ing[v]) ing[u].insert(x);
    par[v] = u;
}

int value(int u) {
    u = get(u);
    return cnt[u] * ing[u].size();
}

void solve() {
    int n, m;
    cin >> n >> m;
    par = cnt = VI(n);
    rep(i, n) {
        par[i] = i;
        cnt[i] = 1;
    }
    set<pair<int, int>> edges;
    ing = vector<set<int>>(n);
    int ans = 0;
    rep(i, m) {
        int u, v;
        cin >> u >> v;
        u--, v--;
        if (edges.count({v, u})) {
            ans -= value(u);
            ans -= value(v);
            join(u, v);
            ans += value(u);
        } else {
            ans += ing[get(v)].insert(u).ss;
        }
        edges.insert({u, v});
        cout << ans << endl;
    }
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL), cout.tie(NULL);
	/*freopen("mincross.in", "r", stdin); */
	/*freopen("mincross.out", "w", stdout); */
	int t = 1;
	/*cin >> t; */
	while (t--) solve();
}

• Subtask 1: 0 / 1
• Subtask 2: 0 / 16
• Subtask 3: 0 / 83