#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using T = tuple<ll, ll, ll>;
//#define int long long
#define Base 41
#define sz(a) (int)a.size()
#define FOR(i, a, b) for ( int i = a ; i <= b ; i++ )
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
#define all(x) x.begin() , x.end()
#define pii pair<int , int>
#define fi first
#define se second
#define Lg(x) 31 - __builtin_clz(x)
#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int MAX = 2e5 + 5;
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
void setupIO(){
#define name "Whisper"
//Phu Trong from Nguyen Tat Thanh High School for gifted student
srand(time(NULL));
cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
//freopen(name".inp", "r", stdin);
//freopen(name".out", "w", stdout);
cout << fixed << setprecision(10);
}
template <class X, class Y>
bool minimize(X &x, const Y &y){
X eps = 1e-9;
if (x > y + eps) {x = y; return 1;}
return 0;
}
template <class X, class Y>
bool maximize(X &x, const Y &y){
X eps = 1e-9;
if (x + eps < y) {x = y; return 1;}
return 0;
}
int N, M;
vector<int> adj[MAX];
int c[MAX];
int tin[MAX], tout[MAX];
int tour[MAX], cnt = 0;
void euler_tour(int u, int p = -1){
tin[u] = ++cnt;
tour[cnt] = u;
for (auto&v : adj[u]) if(v ^ p){
euler_tour(v, u);
}
tout[u] = cnt;
}
int dp[MAX][501];
void Whisper(){
cin >> N >> M;
for (int i = 1; i <= N; ++i){
int p; cin >> p >> c[i];
adj[p].push_back(i);
adj[i].push_back(p);
}
euler_tour(0);
memset(dp, -0x3f, sizeof dp);
dp[cnt + 1][0] = 0;
for (int i = cnt; i >= 1; --i){
int u = tour[i];
for (int v = 0; v <= M; ++v){
maximize(dp[i][v], dp[i + 1][v]);
if (v > 0)
maximize(dp[i][v], dp[tout[u] + 1][v - 1] + c[u]);
}
}
cout << dp[1][M];
}
signed main(){
setupIO();
int Test = 1;
// cin >> Test;
for ( int i = 1 ; i <= Test ; i++ ){
Whisper();
if (i < Test) cout << '\n';
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
92 ms |
398420 KB |
Output is correct |
2 |
Correct |
94 ms |
398420 KB |
Output is correct |
3 |
Correct |
96 ms |
398292 KB |
Output is correct |
4 |
Correct |
97 ms |
398932 KB |
Output is correct |
5 |
Correct |
92 ms |
398876 KB |
Output is correct |
6 |
Correct |
87 ms |
398988 KB |
Output is correct |
7 |
Correct |
253 ms |
407088 KB |
Output is correct |
8 |
Correct |
242 ms |
406920 KB |
Output is correct |
9 |
Correct |
309 ms |
408400 KB |
Output is correct |
10 |
Correct |
353 ms |
409152 KB |
Output is correct |