#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
//#pragma GCC target ("avx2")
//#pragma GCC optimize ("O3")
//#pragma GCC optimize ("unroll-loops")
//#pragma comment (linker, "/STACK: 16777216")
#define f first
#define s second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((int)(x).size())
#define pb push_back
#define mp make_pair
//#define int long long
using namespace std;
using namespace __gnu_pbds;
template <typename T> inline bool umax(T &a, const T &b) { if(a < b) { a = b; return 1; } return 0; }
template <typename T> inline bool umin(T &a, const T &b) { if(a > b) { a = b; return 1; } return 0; }
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
template <typename T> using oset = tree<T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
const ll mod = 998244353;
const ll base = 1e6 + 5;
const int inf = 1e9;
const int MAX = 2e5 + 5;
const int LG = 31;
random_device rd;
mt19937 gen(rd());
uniform_int_distribution<ll> dis(1, inf);
void solve() {
int n, m;
cin >> n >> m;
vector<int> a(n + 1);
vector<vector<int>> g(n + 1);
int root;
for(int i = 1; i <= n; i++) {
int p;
cin >> p >> a[i];
if(!p) {
root = i;
continue;
}
g[p].pb(i);
g[i].pb(p);
}
vector<vector<int>> dp(n + 1, vector<int>(m + 1, -inf));
vector<int> tin(n + 1), tout(n + 1);
vector<int> val(n + 1);
dp[0][0] = 0;
int timer = 1;
function<void(int, int)> dfs = [&](int v, int p) {
tin[v] = timer;
for(auto to : g[v]) {
if(to == p) continue;
dfs(to, v);
}
tout[v] = timer++;
val[tout[v]] = v;
for(int j = 0; j <= m; j++) {
dp[v][j] = max(dp[val[tout[v] - 1]][j], (j > 0? dp[val[tin[v] - 1]][j - 1] + a[v]: -inf));
}
};
dfs(root, 0);
int ans = 0;
// for(int i = 1; i <= n; i++) {
// for(int j = 0; j <= m; j++) {
// cout << dp[i][j] << " ";
// }
// cout << endl;
// }
for(int i = 1; i <= n; i++) umax(ans, dp[i][m]);
cout << ans << '\n';
}
signed main() {
// freopen("skyline.in", "r", stdin); freopen("skyline.out", "w", stdout);
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int ttt = 1;
// cin >> ttt;
while(ttt--) {
solve();
}
return 0;
}
Compilation message
biochips.cpp: In function 'void solve()':
biochips.cpp:44:9: warning: 'root' may be used uninitialized in this function [-Wmaybe-uninitialized]
44 | int root;
| ^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
1 ms |
212 KB |
Output is correct |
| 3 |
Correct |
0 ms |
340 KB |
Output is correct |
| 4 |
Correct |
7 ms |
3456 KB |
Output is correct |
| 5 |
Correct |
9 ms |
4436 KB |
Output is correct |
| 6 |
Correct |
10 ms |
5368 KB |
Output is correct |
| 7 |
Correct |
333 ms |
191932 KB |
Output is correct |
| 8 |
Correct |
368 ms |
191888 KB |
Output is correct |
| 9 |
Correct |
499 ms |
298804 KB |
Output is correct |
| 10 |
Correct |
671 ms |
401744 KB |
Output is correct |
