Submission #673353

#	Time	Username	Problem	Language	Result	Execution time	Memory
673353		viwlesxq	Biochips (IZhO12_biochips)	C++17	90 / 100	339 ms	399540 KiB

biochips

/*#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long 
#define ld long double 
#define pii pair<int, int>
#define pll pair<ll, ll>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vll vector<ll>
#define vii vector<int>
#define vpii vector<pii>
#define vpll vector<pll>
template<class T> bool umin(T& a, const T& b) {return a > b? a = b, true:false;}
template<class T> bool umax(T& a, const T& b) {return a < b? a = b, true:false;}
 
const int N = 2e5+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
 
int n, m, k, timer, root, tin[N], w[N], vv[N], dp[N][505];
vii edges[N];
 
void dfs(int u){
	int tmp = timer;
	for(auto x:edges[u]) dfs(x);
	vv[timer] = w[u];
	tin[timer] = tmp;
	timer++;
}
 
void solve(){
	cin>>n>>m;
	timer = 1;
	for(int i=1;i<=n;i++){
		cin>>k>>w[i];
		edges[k].pb(i);
		if(k == 0) root = i;
	}
	dfs(root);
	for(int i=0;i<=n;i++){
		for(int j=1;j<=m;j++) dp[i][j] = -mod;
	}
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			dp[i][j] = max(dp[i-1][j], dp[tin[i]-1][j-1]+vv[i]);
		}
	}
	
	cout<<dp[n][m]<<endl;
	return;
}
 
 
signed main(){
	fastios
	int t = 0;
	if(!t) solve();
	else {
		cin>>t;
		while (t--) solve();
	}
	return 0;
}*/
#include <bits/stdc++.h>
using namespace std;

using ll = int64_t;
using str = string;

#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#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()

const int N = 2e5 + 1, M = 5e2 + 1, inf = 1e9 + 7;
vector <int> g[N];
int dp[N][M], p[N], x[N], timer = 1, tin[N], arr[N];

void dfs(int v) {
	int in = timer;
	for (int to : g[v]) dfs(to);
	tin[timer] = in;
	arr[timer] = x[v];
	timer++;
}

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n, m;
	cin >> n >> m;
	int root = -1;
	for (int i = 1; i <= n; i++) {
		cin >> p[i] >> x[i];
		if (!p[i]) root = i;
		g[p[i]].pb(i);
	}
	dfs(root);
	for (int i = 0; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			dp[i][j] = -inf;
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			dp[i][j] = max(dp[i - 1][j], dp[tin[i] - 1][j - 1] + arr[i]);
		}
	}
	cout << dp[n][m];
}

• Subtask 1: 90 / 100