Submission #58090

#	Time	Username	Problem	Language	Result	Execution time	Memory
58090		Benq	Biochips (IZhO12_biochips)	C++14	100 / 100	579 ms	13412 KiB

biochips

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 200001;

int N,M, val[MX];
vi child[MX];

vi comb(vi a, vi b) {
    vi c(min(M+1,sz(a)+sz(b)-1));
    F0R(i,sz(a)) for (int j = 0; j < sz(b) && i+j <= M; ++j)
        c[i+j] = max(c[i+j],a[i]+b[j]);
    return c;
}

vi solve(int x) {
    vi cur = {0};
    for (int i: child[x]) cur = comb(cur,solve(i));
    if (sz(cur) == 1) cur.pb(0);
    cur[1] = max(cur[1],val[x]);
    return cur;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N >> M;
    FOR(i,1,N+1) {
        int p,x; cin >> p >> x;
        child[p].pb(i);
        val[i] = x;
    }
    vi v = solve(child[0][0]);
    cout << v[M];
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

• Subtask 1: 100 / 100