Submission #952047

#	Time	Username	Problem	Language	Result	Execution time	Memory
952047		GrindMachine	Worst Reporter 4 (JOI21_worst_reporter4)	C++17	14 / 100	283 ms	197460 KiB

worst_reporter2

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

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
https://codeforces.com/blog/entry/88748?#comment-774017 (thread)
got the key idea, but didnt know how to implement in a clean way

implementation idea:
represent the subtree cost @u as a staircase function using a map
can be merged efficiently using small to large

*/

const int MOD = 1e9 + 7;
const int N = 5e3 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<ll> adj[N];
vector<pll> a(N);
ll dp[N][N];
ll n;

void dfs(ll u){
    trav(v,adj[u]){
        dfs(v);
    }

    auto [h,c] = a[u];

    rev(j,n,1){
        dp[u][j] = c;
        if(j == h) dp[u][j] = 0;

        trav(v,adj[u]){
            dp[u][j] += dp[v][j];
        }

        amin(dp[u][j],dp[u][j+1]);
    }
}

void solve(int test_case)
{
    cin >> n;
    rep1(i,n){
        ll p,h,c; cin >> p >> h >> c;
        if(p != i){
            adj[p].pb(i);
        }
        a[i] = {h,c};
    }

    vector<ll> b;
    rep1(i,n) b.pb(a[i].ff);

    sort(all(b));
    rep1(i,n) a[i].ff = lower_bound(all(b),a[i].ff)-b.begin()+1;

    memset(dp,0x3f,sizeof dp);
    dfs(1);

    ll ans = inf2;
    rep1(j,n) amin(ans,dp[1][j]);
    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 14 / 14
• Subtask 2: 0 / 65
• Subtask 3: 0 / 21