Submission #596428

#	Time	Username	Problem	Language	Result	Execution time	Memory
596428		keta_tsimakuridze	Meetings 2 (JOI21_meetings2)	C++14	0 / 100	8 ms	14380 KiB

meetings2

#include<bits/stdc++.h>
#define f first
#define s second
#define pii pair<int,int>
#define Pii pair<pair<int,int> , pair<int,int> >
using namespace std;
const int N = 2e5 + 5, mod = 1e9 + 7; // !
int t, sz[N], f[N], h;
map<int,int> SZ[N];
int n, c;
int ans[N];
vector<pair<int, pair<int,int> > > x;
vector<int> V[N];
int find(int u,int p, int Sz) {
    for(int i = 0; i< V[u].size(); i++) {
        if(V[u][i] == p|| f[V[u][i]]) continue;
        if(sz[V[u][i]] > Sz / 2) return find(V[u][i], u, Sz);
    }
    return u;
}
void dfs(int u, int p) {
    sz[u] = 1;
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i] == p || f[V[u][i]]) continue;
        dfs(V[u][i], u);
        sz[u] += sz[V[u][i]];
    }
}
void dfs(int u,int p,int P) {
    ++h;
    int sz = SZ[p][u];
    x.push_back({sz, {h, P}});
    ans[min(sz, SZ[P][c]) * 2] = max(ans[min(sz, SZ[P][c]) * 2], h + 1);
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i] == p || f[V[u][i]]) continue;
        dfs(V[u][i], u, P);
    }
    --h;
}
void upd(Pii &mx, pii x) {
    if(x.s == mx.f.s) mx.f = max(mx.f, x);
    else  mx.s = max(mx.s, x);
    if(mx.f.f < mx.s.f) swap(mx.s, mx.f);
}
void decomp(int U) {
    dfs(U, 0);
    c = U;
    for(int i = 0; i < V[c].size(); i++) {
        if(f[V[c][i]] == 0) dfs(V[c][i], c, V[c][i]);
    }

    pair<pii, pii> mx;
    mx = {{-n, 0}, {-n, 0}};
    sort(x.begin(), x.end());
    while(x.size()) {
            int i = x.back().f;
            pii y = x.back().s;
            ans[i * 2] = max(ans[i * 2], y.f + (mx.f.s != y.s ? mx.f.f : mx.s.f ) + 1);
            upd(mx, y);
            x.pop_back();
    }
    return;
    f[c] = 1;
    for(int i = 0; i < V[c].size(); i++) {
        if(!f[V[c][i]])  decomp(V[c][i]);
    }
}
void dfss(int u,int p) {
    sz[u] = 1;
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i] == p) continue;
        dfss(V[u][i], u);
        SZ[u][V[u][i]] = sz[V[u][i]];
        sz[u] += sz[V[u][i]];
    }
    SZ[u][p] = n - sz[u];
}
main(){
    cin >> n;
    for(int i = 1; i < n; i++) {
        int u, v;
        cin >> u >> v;
        V[u].push_back(v);
        V[v].push_back(u);
    }
    dfss(1, 0);
    for(int i = 1; i <= n; i++)
    decomp(i);
    for(int i = n; i >= 1; i--) {
        ans[i] = (i % 2 == 0 ? max(ans[i], ans[i + 2]) : 1);
    }
    for(int i = 1; i <= n; i++) {
        cout << ans[i] << "\n";
    }
 }

Compilation message (stderr)

meetings2.cpp: In function 'int find(int, int, int)':
meetings2.cpp:15:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |     for(int i = 0; i< V[u].size(); i++) {
      |                    ~^~~~~~~~~~~~~
meetings2.cpp: In function 'void dfs(int, int)':
meetings2.cpp:23:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
meetings2.cpp: In function 'void dfs(int, int, int)':
meetings2.cpp:34:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
meetings2.cpp: In function 'void decomp(int)':
meetings2.cpp:48:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |     for(int i = 0; i < V[c].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
meetings2.cpp:64:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |     for(int i = 0; i < V[c].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
meetings2.cpp: In function 'void dfss(int, int)':
meetings2.cpp:70:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
meetings2.cpp: At global scope:
meetings2.cpp:78:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   78 | main(){
      | ^~~~

• Subtask 1: 0 / 4
• Subtask 2: 0 / 16
• Subtask 3: 0 / 80