Submission #411184

#	Time	Username	Problem	Language	Result	Execution time	Memory
411184		Blagojce	Chase (CEOI17_chase)	C++11	30 / 100	895 ms	331444 KiB

chase

#include <bits/stdc++.h>
#define fr(i, n, m) for(int i = (n); i < (m); i ++)
#define pb push_back
#define st first
#define nd second
#define pq priority_queue
#define all(x) begin(x), end(x)


using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const int i_inf = 1e9;
const ll inf = 1e18;
const ll mod = 1e9+7;
const ld eps = 1e-13;
const ld pi  = 3.14159265359;

mt19937 _rand(time(NULL));
clock_t z;

const int mxn = 2e5+5;

int n, v;
ll a[mxn];

ll nsum[mxn];



vector<int> g[mxn];

ll ans = 0;


ll dp1[mxn][101][2];
ll dp2[mxn][101][2];

void dfs(int u, int p){
	for(auto e : g[u]){
		if(e == p) continue;
		dfs(e, u);
	}
	
	fr(k, 1, 101){
		for(auto e : g[u]){
			dp1[u][k][0] = max(dp1[u][k][0], max(dp1[e][k][0], dp1[e][k][1] - a[u])); 
			dp1[u][k][1] = max(dp1[u][k][1], max(dp1[e][k-1][0], dp1[e][k-1][1]-a[u])+nsum[u]);
		}
	}
	ll MX = 0;
	fr(k, 0, 101){
		MX = max(MX, dp1[u][k][0]);
		dp1[u][k][0] = MX;
	}
	MX = 0;
	fr(k, 0, 101){
		MX = max(MX, dp1[u][k][1]);
		dp1[u][k][1] = MX;
	}
	
	
	fr(k, 1, 101){
		for(auto e : g[u]){
			ll mx1 = max(dp2[e][k][0], dp2[e][k][1]);
			ll mx2 = max(dp2[e][k-1][0], dp2[e][k-1][1]);
			
			dp2[u][k][0] = max(dp2[u][k][0], mx1);
			dp2[u][k][1] = max(dp2[u][k][1], mx2 + nsum[u] - a[e]);
		}
	}
	
	MX = 0;
	fr(k, 0, 101){
		MX = max(MX, dp2[u][k][0]);
		dp2[u][k][0] = MX;
	}
	MX = 0;
	fr(k, 0, 101){
		MX = max(MX, dp2[u][k][1]);
		dp2[u][k][1] = MX;
	}
}
ll f(int u){
	ll ret = 0;
	fr(i, 0, v+1){
		ret = max(ret, dp1[u][i][0] + dp2[u][v-i][0]);
	}
	fr(i, 0, v+1){
		ll tmp = dp1[u][i][1] + dp2[u][v-i+1][1];
		ret = max(ret, dp1[u][i][1] + dp2[u][v-i+1][1] - nsum[u]);
	
	}
	return ret;



}



void solve(){	
	cin >> n >> v;
	fr(i, 0, n){
		cin >> a[i];
	}
	fr(i, 0, n-1){
		int u, v;
		cin >> u >> v;
		--u, --v;
		g[u].pb(v);
		g[v].pb(u);
	}
	fr(i, 0, n){
		nsum[i] = 0;
		for(auto u : g[i]){
			nsum[i] += a[u];
		}
	}
	dfs(0, 0);
	ll ans = 0;
	fr(i, 0, v+1) ans = max(ans, dp1[0][i][0]);
	fr(i, 0, v+1) ans = max(ans, dp1[0][i][1]);
	cout<<ans<<endl;
	
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	solve();
}/*
12 2
2 3 3 8 1 5 6 7 8 3 5 4
2 1
2 7
3 4
4 7
7 6
5 6
6 8
6 9
7 10
10 11
10 12
ll ans = 0;
	fr(i, 0, n){
		ans = max(ans, f(i));
	}
	
	cout<<ans<<endl;
*/

Compilation message (stderr)

chase.cpp: In function 'll f(int)':
chase.cpp:91:6: warning: unused variable 'tmp' [-Wunused-variable]
   91 |   ll tmp = dp1[u][i][1] + dp2[u][v-i+1][1];
      |      ^~~

• Subtask 1: 0 / 20
• Subtask 2: 0 / 20
• Subtask 3: 30 / 30
• Subtask 4: 0 / 30