Submission #371214

#	Time	Username	Problem	Language	Result	Execution time	Memory
371214		hollwo_pelw	Making Friends on Joitter is Fun (JOI20_joitter2)	C++17	0 / 100	12 ms	14444 KiB

joitter2

/*
 /+==================================================+\
//+--------------------------------------------------+\\
|.|\\...>>>>>>> Hollwo_Pelw(ass) 's code <<<<<<<...//|.|
\\+--------------------------------------------------+//
 \+==================================================+/
*/
#include <bits/stdc++.h>
using namespace std;
// type
typedef long long ll;
typedef long double ld;
// pair
#define F                   first
#define S                   second
#define pii                 pair<int, int>
#define pll                 pair<ll, ll>
#define pdd                 pair<ld, ld>
// vector & !!?(string)
#define eb                  emplace_back
#define pb                  push_back
#define all(a)              a.begin(), a.end()
#define rall(a)             a.rbegin(), a.rend()
#define sz(a)               a.size()
#define len(a)              a.length()
// I/O
#define open(file, in, out) if (fopen(file in, "r")) {        \
                                freopen(file in, "r", stdin);  \
                                freopen(file out, "w", stdout); \
                            }
#define FAST_IO             std::ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define setpre(n)           fixed << setprecision(n)        
bool endline = false;
template<class T>
istream& operator >> (istream& inp, vector<T>& v){
    for (auto& it : v) inp >> it;
    return inp;
}
template<class T>
ostream& operator << (ostream& out, vector<T>& v){
    for (auto& it : v) out << it << (endline ? "\n" : " ");
    return out;
}
template<class T, class U>
istream& operator >> (istream& inp, pair<T, U>& v){
    inp >> v.F >> v.S;
    return inp;
}
template<class T, class U>
ostream& operator << (ostream& out, pair<T, U>& v){
    out << v.F << ' ' << v.S;
    return out;
}
#define debug(x)            cout << #x << " : " << endl << x << endl;
#define Ptest(x)            return cout << x << endl, (void) 0;
// geometry calculate
#define pi                  acos(-1.0)
#define g_sin(a)            sin(a*pi/180)
#define g_cos(a)            cos(a*pi/180)
#define g_tan(a)            tan(a*pi/180)
// set val
#define ms0(a)              memset(a,        0, sizeof(a));
#define ms1(a)              memset(a,        1, sizeof(a));
#define msn1(a)             memset(a,       -1, sizeof(a));
#define msinf(a)            memset(a, 0x3f3f3f, sizeof(a));
// constant
const int mod1 = 998244353, mod = 1e9 + 7;
const int MAXN = 1e5 + 5 , MAXM = 3e5 + 5;
const int inf = 2e9; const ll linf = 1e18;
// code
#define left node << 1, tl, tm
#define right node << 1 | 1, tm + 1, tr
// #define int long long

int n, m, par[MAXN];
ll ans, sz[MAXN];
set<int> adj[MAXN], radj[MAXN], fol[MAXN];
queue<pii> to_merge;
void weakedge(int u, int v){
    adj[u].insert(v);
    radj[v].insert(u);
    // if now strong 
    if (adj[v].count(u))
        to_merge.push({u, v});
}

int find(int u){
    return par[u] = (par[u] == u ? u : par[u]);
}

int dsize(int u){
    return fol[u].size() + radj[u].size() + adj[u].size();
}

void merge(int u, int v){
    if (u == v) return ;
    if (dsize(u) < dsize(v))
        swap(u, v);
    ans += sz[u] * fol[v].size() + sz[v] * fol[u].size();
    par[v] = u;
    sz[u] += sz[v];
    for (auto f : fol[v]){
        if (fol[u].count(f))
            ans -= sz[u];
        else 
            fol[u].insert(f);
    }
    adj[u].erase(v), radj[v].erase(u);
    adj[v].erase(u), radj[u].erase(v);
    for (auto f : adj[v]){
        radj[f].erase(v);
        weakedge(u, f);
    }
    for (auto f : radj[v]){
        adj[f].erase(u);
        weakedge(f, u);
    }
}

void Solve(){
    cin >> n >> m;
    for (int i = 1; i <= n; i++){
        par[i] = i;
        sz[i] = 1;
        fol[i].insert(i);
    }
    while(m --){
        int u, v;
        cin >> u >> v;
        int pu = u, pv = v;
        if (pu != pv && !fol[pv].count(u)){
            fol[pv].insert(u);
            ans += sz[pv];
            weakedge(pu, pv);
            while(!to_merge.empty()){
                auto[uu, vv] = to_merge.front();
                to_merge.pop();
                merge(uu, vv);
                // cout << "MERGE " << uu << ' ' << vv << endl;
            }
        }
        cout << ans << "\n";
    }
}

signed main(){
    open("", ".inp", ".out");
    FAST_IO; int TC = 1;
    //cin >> TC;
    while(TC--) Solve();
    return 0;
}
/*
./-=====>>><<<-------- DEBUG -------->>><<<=====-\.
/.................................................\

+====================== INP ======================+


+====================== OUT ======================+


\................................................./
.\-=====>>><<<--------= END =-------->>><<<=====-/.
*/

Compilation message (stderr)

joitter2.cpp: In function 'int main()':
joitter2.cpp:28:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   28 |                                 freopen(file in, "r", stdin);  \
      |                                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
joitter2.cpp:147:5: note: in expansion of macro 'open'
  147 |     open("", ".inp", ".out");
      |     ^~~~
joitter2.cpp:29:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   29 |                                 freopen(file out, "w", stdout); \
      |                                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
joitter2.cpp:147:5: note: in expansion of macro 'open'
  147 |     open("", ".inp", ".out");
      |     ^~~~

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