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Submission #99791

# Submission time Handle Problem Language Result Execution time Memory
99791 2019-03-07T10:32:09 Z Retro3014 Beads and wires (APIO14_beads) C++17
100 / 100
 257 ms 25740 KB 
#include <bits/stdc++.h>

#define pb push_back
#define all(v) ((v).begin(), (v).end())
#define sortv(v) sort(all(v))
#define sz(v) ((int)(v).size())
#define uniqv(v) (v).erase(unique(all(v)), (v).end())
#define umax(a, b) (a)=max((a), (b))
#define umin(a, b) (a)=min((a), (b))
#define FOR(i,a,b) for(int i = (a); i <= (b); i++)
#define rep(i,n) FOR(i,1,n)
#define rep0(i,n) FOR(i,0,(int)(n)-1)
#define FI first
#define SE second
#define INF 2000000000
#define INFLL 1000000000000000000LL


using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<int, ll> pil;

const int MAX_N = 200000;

int N;
vector<pil> gp[MAX_N+1];
int p[MAX_N+1];
int c[MAX_N+1];
ll dp[MAX_N+1][4];


void dfs(int x){
	for(auto i : gp[x]){
		if(i.first==p[x])	continue;
		p[i.first] = x;
		c[i.first] = i.second;
		dfs(i.first);
	}
	for(auto i : gp[x])	{
		if(i.first==p[x])	continue;
		dp[x][0] += max(dp[i.first][0], dp[i.first][2]);
	}
	ll mx = -INF;
	dp[x][1] = dp[x][2] = dp[x][3] = -INF;
	for(auto i : gp[x]){
		if(i.first==p[x])	continue;
		mx = max(mx, max(dp[i.first][1], dp[i.first][3]) - max(dp[i.first][0], dp[i.first][2]));
	}
	dp[x][1] = dp[x][0] + mx;
	ll mx1 = -INF, mx2 = -INF;
	for(auto i : gp[x]){
		if(i.first==p[x])	continue;
		dp[x][1] = max(dp[x][1], dp[x][0] + mx1 + dp[i.first][1] + i.second - max(dp[i.first][0], dp[i.first][2]));
		dp[x][1] = max(dp[x][1], dp[x][0] + mx2 + dp[i.first][0] + i.second - max(dp[i.first][0], dp[i.first][2]));
		dp[x][1] = max(dp[x][1], dp[x][0] + mx1 + dp[i.first][0] + i.second - max(dp[i.first][0], dp[i.first][2]));
		mx1 = max(mx1, dp[i.first][0] + i.second - max(dp[i.first][0], dp[i.first][2]));
		mx2 = max(mx2, dp[i.first][1] + i.second - max(dp[i.first][0], dp[i.first][2]));
	}
	for(auto i : gp[x]){
		if(i.first==p[x])	continue;
		dp[x][2] = max(dp[x][2], dp[x][0] + dp[i.first][0] + i.second - max(dp[i.first][0], dp[i.first][2]) + c[x]);
	}
	for(auto i : gp[x]){
		if(i.first==p[x])	continue;
		dp[x][3] = max(dp[x][3], c[x] + dp[x][0] + dp[i.first][1] + i.second - max(dp[i.first][0], dp[i.first][2]));
	}
	/*cout<<x<<endl;
	for(int i=0; i<4; i++){
		cout<<dp[x][i]<<' ';
	}cout<<endl;*/
}

int main(){
	scanf("%d", &N);
	for(int i=0; i<N-1; i++){
		int x, y; ll z;
		scanf("%d%d%lld", &x, &y, &z);
		gp[x].push_back({y, z}); gp[y].push_back({x, z});
	}
	dfs(1);
	cout<<max(dp[1][0], dp[1][1]);
	return 0;
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:76:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
beads.cpp:79:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%lld", &x, &y, &z);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5120 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 5 ms 4992 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 5 ms 4992 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 5 ms 5120 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5120 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 5 ms 4992 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 5 ms 4992 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 5 ms 5120 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 6 ms 4992 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 7 ms 5120 KB Output is correct
22 Correct 7 ms 5120 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5120 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 5 ms 4992 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 5 ms 4992 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 5 ms 5120 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 6 ms 4992 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 7 ms 5120 KB Output is correct
22 Correct 7 ms 5120 KB Output is correct
23 Correct 9 ms 5504 KB Output is correct
24 Correct 9 ms 5504 KB Output is correct
25 Correct 9 ms 5504 KB Output is correct
26 Correct 13 ms 5888 KB Output is correct
27 Correct 12 ms 6016 KB Output is correct
28 Correct 11 ms 5968 KB Output is correct
29 Correct 12 ms 5888 KB Output is correct
30 Correct 11 ms 5888 KB Output is correct
31 Correct 12 ms 6144 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5120 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 5 ms 4992 KB Output is correct
5 Correct 6 ms 5120 KB Output is correct
6 Correct 5 ms 4992 KB Output is correct
7 Correct 6 ms 5120 KB Output is correct
8 Correct 6 ms 4992 KB Output is correct
9 Correct 5 ms 5120 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 4992 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 6 ms 4992 KB Output is correct
17 Correct 6 ms 4992 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 7 ms 5120 KB Output is correct
22 Correct 7 ms 5120 KB Output is correct
23 Correct 9 ms 5504 KB Output is correct
24 Correct 9 ms 5504 KB Output is correct
25 Correct 9 ms 5504 KB Output is correct
26 Correct 13 ms 5888 KB Output is correct
27 Correct 12 ms 6016 KB Output is correct
28 Correct 11 ms 5968 KB Output is correct
29 Correct 12 ms 5888 KB Output is correct
30 Correct 11 ms 5888 KB Output is correct
31 Correct 12 ms 6144 KB Output is correct
32 Correct 48 ms 9592 KB Output is correct
33 Correct 46 ms 9592 KB Output is correct
34 Correct 48 ms 9592 KB Output is correct
35 Correct 252 ms 23068 KB Output is correct
36 Correct 257 ms 23160 KB Output is correct
37 Correct 245 ms 23160 KB Output is correct
38 Correct 163 ms 22364 KB Output is correct
39 Correct 157 ms 22212 KB Output is correct
40 Correct 179 ms 22368 KB Output is correct
41 Correct 244 ms 25740 KB Output is correct