Submission #758767

#	Time	Username	Problem	Language	Result	Execution time	Memory
758767		keta_tsimakuridze	Pastiri (COI20_pastiri)	C++14	100 / 100	620 ms	94744 KiB

pastiri

#include<bits/stdc++.h>
#define f first
#define s second

#define pii pair<int,int>
using namespace std;
const int N = 5e5 + 5, mod = 1e9 + 7; // !
int n, d[N];
vector<int> V[N], A;
struct node {
    int A, B, ans;
} x[N];
void dfs(int u, int p) {
    for(int i = 0; i < V[u].size(); i++) {
        int v = V[u][i];
        if(v == p) continue;
        dfs(v, u);
        if(x[v].A + 1 > d[u]) {
            x[v].ans++; A.push_back(v);
//            cout << "++" << v << endl;
            x[v].A = -n;
            x[v].B = d[v];
        }
        x[u].A = max(x[u].A, x[v].A + 1);
        x[u].B = max(x[u].B, x[v].B - 1);
        x[u].ans += x[v].ans;
    }
    if(x[u].A <= x[u].B) x[u].A = -n - 5;
    if(d[u] == 0 && x[u].B < 0) x[u].A = max(x[u].A, 0);
//    cout << u <<" " << x[u].A << " " << x[u].B << " " << x[u].ans << endl;
}
main(){
    int k;
    cin >> n >> k;
    for(int i = 2; i <= n; i++) {
        int u, v;
        cin >> u >> v;
        V[u].push_back(v);
        V[v].push_back(u);
    }
    for(int u = 1; u <= n; u++) d[u] = n, x[u].A = -n - 5, x[u].B = -n-5, x[u].ans = 0;
    queue<int> q;
    while(k--) {
        int x;
        cin >> x;
        d[x] = 0;
        q.push(x);
    }
    while(q.size()) {
        int u = q.front();
        q.pop();
        for(int i = 0; i < V[u].size(); i++) {
            if(d[V[u][i]] > d[u] + 1) d[V[u][i]] = d[u] + 1, q.push(V[u][i]);
        }
    }
    dfs(1, 0);
    if(x[1].A > -1) ++x[1].ans, A.push_back(1);
    cout << A.size() << "\n";
    sort(A.begin(), A.end());
    for(int i = 0; i < A.size(); i++) cout << A[i] << " "; cout << endl;

 }

Compilation message (stderr)

pastiri.cpp: In function 'void dfs(int, int)':
pastiri.cpp:14:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
pastiri.cpp: At global scope:
pastiri.cpp:32:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   32 | main(){
      | ^~~~
pastiri.cpp: In function 'int main()':
pastiri.cpp:52:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |         for(int i = 0; i < V[u].size(); i++) {
      |                        ~~^~~~~~~~~~~~~
pastiri.cpp:60:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |     for(int i = 0; i < A.size(); i++) cout << A[i] << " "; cout << endl;
      |                    ~~^~~~~~~~~~
pastiri.cpp:60:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   60 |     for(int i = 0; i < A.size(); i++) cout << A[i] << " "; cout << endl;
      |     ^~~
pastiri.cpp:60:60: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   60 |     for(int i = 0; i < A.size(); i++) cout << A[i] << " "; cout << endl;
      |                                                            ^~~~

• Subtask 1: 8 / 8
• Subtask 2: 18 / 18
• Subtask 3: 23 / 23
• Subtask 4: 51 / 51