Submission #92929

#	Time	Username	Problem	Language	Result	Execution time	Memory
92929		jasony123123	Paprike (COI18_paprike)	C++11	100 / 100	78 ms	17784 KiB

paprike

#define _CRT_SECURE_NO_WARNINGS
#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;

#define FOR(i,start,end) for(int i=start;i<(int)(end);i++)
#define FORE(i,start,end) for(int i=start;i<=(int)end;i++)
#define RFOR(i,start,end) for(int i = start; i>end; i--)
#define RFORE(i,start,end) for(int i = start; i>=end; i--)
#define all(a) a.begin(), a.end()
#define mt make_tuple
#define mp make_pair
#define v vector
#define sf scanf
#define pf printf
#define dvar(x) cout << #x << " := " << x << "\n"
#define darr(x,n) FOR(i,0,n) cout << #x << "[" << i << "]" << " := " << x[i] << "\n"

typedef long long ll;
typedef long double ld;
typedef pair<int, int > pii;
typedef pair<ll, ll> pll;
//template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> void minn(T &a, T b) { a = min(a, b); }
template<class T> void maxx(T &a, T b) { a = max(a, b); }

void io() {
#ifdef LOCAL_PROJECT 
	freopen("input.in", "r", stdin); freopen("output.out", "w", stdout);
#else 
	/* online submission */

#endif 
	ios_base::sync_with_stdio(false); cin.tie(NULL);
}

const ll MOD = 1000000007LL;
const ll PRIME = 105943LL;
const ll INF = 1e18;
/****************************COI 2018 P1-Paprike*******************************/

const int MAXN = 1e5 + 99;
int N, K;
int H[MAXN];
v<int> adj[MAXN];
int cuts = 0;

int go(int x, int p) {
	v<int> chi;
	for (auto c : adj[x]) if (c != p)
		chi.push_back(go(c, x));
	sort(all(chi));
	int cur = H[x], i = -1;
	while (i + 1<chi.size() && cur + chi[i + 1] <= K) cur += chi[++i];
	cuts += chi.size() - 1 - i;
	return cur;
}

int main() {
	io();
	cin >> N >> K;
	FORE(i, 1, N) cin >> H[i];
	FOR(i, 0, N - 1) {
		int a, b;
		cin >> a >> b;
		adj[a].push_back(b), adj[b].push_back(a);
	}
	go(1, -1);
	cout << cuts << "\n";
	return 0;
}

Compilation message (stderr)

paprike.cpp: In function 'int go(int, int)':
paprike.cpp:56:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while (i + 1<chi.size() && cur + chi[i + 1] <= K) cur += chi[++i];
         ~~~~~^~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 27 / 27
• Subtask 4: 49 / 49