#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
#define sz(x) (int)x.size()
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt __builtin_popcount
#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
// template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(Tree <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
// for random generations
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
// mt19937 myrand(131);
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
fastIO();
// if(str == "input") {
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
// } else if(str != "") {
// freopen((str + ".in").c_str(), "r", stdin);
// freopen((str + ".out").c_str(), "w", stdout);
// }
}
const int N = 2e5 + 10;
vector<int> adj[N];
int n, dp[N], answ;
bool is_bomb[N];
void dfs(int node, int parent) {
if(parent) {
if(is_bomb[node]) {
dp[node] = 1;
} else {
dp[node] = 0;
}
} else {
dp[node] = 0;
}
for(auto i: adj[node]) {
if(i == parent) continue;
dfs(i, node);
}
int is_black = 0, ans = 0;
for(auto i: adj[node]) {
if(i == parent) continue;
if(dp[i] > 0) {
is_black++;
}
ans += max(0, dp[i]);
}
if(is_black) {
ans -= dp[node];
}
if(!parent && is_black >= 2 && is_bomb[node]) {
ans -= 2;
}
dp[node] = max(dp[node], ans);
}
void dfs1(int node, int parent, int up_dp) {
int is_black = 0, ans = 0;
for(auto i: adj[node]) {
if(i == parent) continue;
if(dp[i] > 0) {
is_black++;
}
ans += max(0, dp[i]);
}
if(up_dp > 0) {
is_black++;
}
ans += max(0, up_dp);
if(is_black >= 2) {
answ = max(answ, ans - is_bomb[node]);
} else {
answ = max(answ, ans + is_bomb[node]);
}
if(is_black) {
ans -= is_bomb[node];
}
for(auto i: adj[node]) {
if(i == parent) continue;
int add = 0;
if(dp[i] > 0) {
is_black--;
if(is_black == 0) {
add = is_bomb[node];
}
}
ans -= max(0, dp[i]);
dfs1(i, node, ans + add);
ans += max(0, dp[i]);
if(dp[i] > 0) {
is_black++;
}
}
}
void solve_() {
cin >> n;
for(int i = 1; i <= n - 1; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
string s; cin >> s;
vector<int> can;
for(int i = 0; i < n; i++) {
if(s[i] == '1') {
can.push_back(i + 1);
is_bomb[i + 1] = true;
}
}
//
dfs(1, 0);
answ = max(answ, dp[1] + is_bomb[1]);
dfs1(1, 0, 0);
cout << answ << '\n';
}
int main() {
setIO();
auto solve = [&](int test_case)-> void {
for(int i = 1; i <= test_case; i++) {
solve_();
}
};
int test_cases = 1;
// cin >> test_cases;
solve(test_cases);
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 4 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 5 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 6 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 8 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 9 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 10 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 11 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 12 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 13 |
Incorrect |
2 ms |
4948 KB |
Output isn't correct |
| 14 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 4 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 5 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 6 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 8 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 9 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 10 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 11 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 12 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 13 |
Incorrect |
2 ms |
4948 KB |
Output isn't correct |
| 14 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 4 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 5 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 6 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 8 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 9 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 10 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 11 |
Correct |
2 ms |
4948 KB |
Output is correct |
| 12 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 13 |
Incorrect |
2 ms |
4948 KB |
Output isn't correct |
| 14 |
Halted |
0 ms |
0 KB |
- |
