Submission #742426

# Submission time Handle Problem Language Result Execution time Memory
742426 2023-05-16T09:06:04 Z penguin133 The Xana coup (BOI21_xanadu) C++17
100 / 100
106 ms 26696 KB
#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

int memo[100005][2][2], n;
int A[100005];
vector <int> adj[100005];

bool cmp(pi a, pi b){
	return a.fi - a.se < b.fi - b.se;
}

int dp(int x, int par, int f, int f2){
	if(memo[x][f][f2] != -1)return memo[x][f][f2];
	int ok = A[x];
	if(f)ok = !ok;
	if(f2)ok = !ok;
	int ans = 2e9;
	vector <pi> cand;
	int stuf = 0;
	for(auto i : adj[x]){
		if(i == par)continue;
		int x1 = dp(i, x, 1, f);
		int x2 = dp(i, x, 0, f);
		cand.push_back({x1, x2});
		stuf += x2;
	}
	sort(cand.begin(), cand.end(), cmp);
	for(int i=ok-1;i<(int)cand.size();i+=2){
		if(i > 0)stuf += cand[i-1].fi - cand[i-1].se;
		if(i >= 0)stuf += cand[i].fi - cand[i].se;
		ans = min(ans, stuf);
	}
	if(f)ans++;
	return memo[x][f][f2] = ans;
}

void solve(){
	cin >> n;
	for(int i=1;i<n;i++){
		int a, b; cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	for(int i=1;i<=n;i++)cin >> A[i];
	memset(memo, -1, sizeof(memo));
	int tmp = min(dp(1, -1, 0, 0), dp(1, -1, 1, 0));
	if(tmp > n)cout << "impossible";
	else cout << tmp;
}

main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int tc = 1;
	//cin >> tc;
	for(int tc1=1;tc1<=tc;tc1++){
		// cout << "Case #" << tc1 << ": ";
		solve();
	}
}

Compilation message

xanadu.cpp:61:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   61 | main(){
      | ^~~~
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5716 KB Output is correct
2 Correct 3 ms 5716 KB Output is correct
3 Correct 3 ms 5716 KB Output is correct
4 Correct 3 ms 5716 KB Output is correct
5 Correct 3 ms 5716 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5716 KB Output is correct
2 Correct 3 ms 5716 KB Output is correct
3 Correct 3 ms 5716 KB Output is correct
4 Correct 3 ms 5716 KB Output is correct
5 Correct 3 ms 5716 KB Output is correct
6 Correct 3 ms 5716 KB Output is correct
7 Correct 3 ms 5716 KB Output is correct
8 Correct 3 ms 5716 KB Output is correct
9 Correct 3 ms 5716 KB Output is correct
10 Correct 3 ms 5716 KB Output is correct
11 Correct 4 ms 5844 KB Output is correct
12 Correct 3 ms 5716 KB Output is correct
13 Correct 3 ms 5716 KB Output is correct
14 Correct 3 ms 5716 KB Output is correct
15 Correct 3 ms 5716 KB Output is correct
16 Correct 4 ms 5732 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 82 ms 25312 KB Output is correct
2 Correct 75 ms 25052 KB Output is correct
3 Correct 80 ms 25348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 77 ms 25176 KB Output is correct
2 Correct 81 ms 25008 KB Output is correct
3 Correct 80 ms 25328 KB Output is correct
4 Correct 73 ms 10088 KB Output is correct
5 Correct 78 ms 10460 KB Output is correct
6 Correct 81 ms 10552 KB Output is correct
7 Correct 3 ms 5716 KB Output is correct
8 Correct 27 ms 7332 KB Output is correct
9 Correct 84 ms 10316 KB Output is correct
10 Correct 89 ms 10340 KB Output is correct
11 Correct 91 ms 11468 KB Output is correct
12 Correct 95 ms 11580 KB Output is correct
13 Correct 69 ms 10572 KB Output is correct
14 Correct 80 ms 10876 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5716 KB Output is correct
2 Correct 3 ms 5716 KB Output is correct
3 Correct 3 ms 5716 KB Output is correct
4 Correct 3 ms 5716 KB Output is correct
5 Correct 3 ms 5716 KB Output is correct
6 Correct 3 ms 5716 KB Output is correct
7 Correct 3 ms 5716 KB Output is correct
8 Correct 3 ms 5716 KB Output is correct
9 Correct 3 ms 5716 KB Output is correct
10 Correct 3 ms 5716 KB Output is correct
11 Correct 4 ms 5844 KB Output is correct
12 Correct 3 ms 5716 KB Output is correct
13 Correct 3 ms 5716 KB Output is correct
14 Correct 3 ms 5716 KB Output is correct
15 Correct 3 ms 5716 KB Output is correct
16 Correct 4 ms 5732 KB Output is correct
17 Correct 82 ms 25312 KB Output is correct
18 Correct 75 ms 25052 KB Output is correct
19 Correct 80 ms 25348 KB Output is correct
20 Correct 77 ms 25176 KB Output is correct
21 Correct 81 ms 25008 KB Output is correct
22 Correct 80 ms 25328 KB Output is correct
23 Correct 73 ms 10088 KB Output is correct
24 Correct 78 ms 10460 KB Output is correct
25 Correct 81 ms 10552 KB Output is correct
26 Correct 3 ms 5716 KB Output is correct
27 Correct 27 ms 7332 KB Output is correct
28 Correct 84 ms 10316 KB Output is correct
29 Correct 89 ms 10340 KB Output is correct
30 Correct 91 ms 11468 KB Output is correct
31 Correct 95 ms 11580 KB Output is correct
32 Correct 69 ms 10572 KB Output is correct
33 Correct 80 ms 10876 KB Output is correct
34 Correct 4 ms 5716 KB Output is correct
35 Correct 3 ms 5716 KB Output is correct
36 Correct 4 ms 5756 KB Output is correct
37 Correct 3 ms 5752 KB Output is correct
38 Correct 3 ms 5716 KB Output is correct
39 Correct 3 ms 5716 KB Output is correct
40 Correct 3 ms 5716 KB Output is correct
41 Correct 3 ms 5756 KB Output is correct
42 Correct 3 ms 5716 KB Output is correct
43 Correct 3 ms 5752 KB Output is correct
44 Correct 3 ms 5716 KB Output is correct
45 Correct 88 ms 26484 KB Output is correct
46 Correct 85 ms 26348 KB Output is correct
47 Correct 87 ms 26696 KB Output is correct
48 Correct 68 ms 11272 KB Output is correct
49 Correct 85 ms 11812 KB Output is correct
50 Correct 93 ms 11816 KB Output is correct
51 Correct 3 ms 5760 KB Output is correct
52 Correct 26 ms 7752 KB Output is correct
53 Correct 76 ms 11592 KB Output is correct
54 Correct 81 ms 11772 KB Output is correct
55 Correct 79 ms 12612 KB Output is correct
56 Correct 87 ms 12948 KB Output is correct
57 Correct 81 ms 11824 KB Output is correct
58 Correct 98 ms 12156 KB Output is correct
59 Correct 29 ms 7688 KB Output is correct
60 Correct 74 ms 11000 KB Output is correct
61 Correct 79 ms 11596 KB Output is correct
62 Correct 96 ms 11592 KB Output is correct
63 Correct 106 ms 11700 KB Output is correct
64 Correct 86 ms 11584 KB Output is correct
65 Correct 69 ms 12112 KB Output is correct
66 Correct 70 ms 12156 KB Output is correct
67 Correct 78 ms 15420 KB Output is correct
68 Correct 87 ms 15512 KB Output is correct
69 Correct 81 ms 15480 KB Output is correct
70 Correct 89 ms 15452 KB Output is correct