Submission #256075

#	Time	Username	Problem	Language	Result	Execution time	Memory
256075		anubhavdhar	Cat in a tree (BOI17_catinatree)	C++14	0 / 100	1 ms	384 KiB

catinatree

#include<bits/stdc++.h>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ff first 
#define ss second
#define vi vector<int>
#define vl vector<ll>
#define vii vector<pii>
#define vll vector<pll>
#define FOR(i,N) for(i=0;i<(N);++i)
#define FORe(i,N) for(i=1;i<=(N);++i)
#define FORr(i,a,b) for(i=(a);i<(b);++i)
#define FORrev(i,N) for(i=(N);i>=0;--i)
#define F0R(i,N) for(int i=0;i<(N);++i)
#define F0Re(i,N) for(int i=1;i<=(N);++i)
#define F0Rr(i,a,b) for(ll i=(a);i<(b);++i)
#define F0Rrev(i,N) for(int i=(N);i>=0;--i)
#define all(v) (v).begin(),(v).end()
#define dbgLine cerr<<" LINE : "<<__LINE__<<"\n"
#define ldd long double

using namespace std;

const int Alp = 26;
const int __PRECISION = 9;
const int inf = 1e9 + 8;

const ldd PI = acos(-1);
const ldd EPS = 1e-7;

const ll MOD = 1e9 + 7;
const ll MAXN = 1507;//2e5 + 5;
const ll ROOTN = 320;
const ll LOGN = 18;
const ll INF = 1e18 + 1022;

int N, D, dis[MAXN], cat_cnt, mxdep[MAXN], dp[MAXN][MAXN];
vi g[MAXN];

void dfs(int a, int par)
{
    for(int b : g[a])
        if(b != par)
            dfs(b, a), dp[a][0] += dp[b][D-1];

    F0Re(i, D-1)
    {
        int x = min(i, D-i);
        int y = D-x, sm = 0, mx = -inf;
        for(int b : g[a])
            if(b != par)
                sm += dp[b][y-1], mx = max(dp[b][x-1] - dp[b][y-1], mx);
        dp[a][i] = sm + mx;
    }

    F0R(i, D)
        cat_cnt = max(cat_cnt, dp[a][i]);
}

signed main()
{

	/*
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	*/

	/*
	int test_case_number;
	cin>>test_case_number;
	while(test_case_number--)
		test_case();
	*/

	cin>>N>>D;

    if(D >= N)
    {
        cout<<"1\n";
        exit(0);
    }
    if(D == 1)
    {
        cout<<N<<'\n';
        exit(0);
    }

	cat_cnt = 0;

	F0Re(i, N)
		dis[i] = inf, mxdep[i] = 0;

    F0Re(i, N)
        F0R(j, D)
            dp[i][j] = (j==0) ? 1 : 0;

	F0Re(i, N-1)
	{
		int j;
		cin>>j;
		g[i+1].pb(j+1);
		g[j+1].pb(i+1);
	}

    // F0Re(i, N)
    //     sort(all(g[i]), cmp);

    dfs(1, -1);

 
 	cout<<cat_cnt<<'\n';

	return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 40
• Subtask 3: 0 / 49