#include <bits/stdc++.h>
// #pragma GCC optimize ("Ofast,unroll-loops")
// #pragma GCC target ("avx2")
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pp;
#define per(i,r,l) for(int i = (r); i >= (l); i--)
#define rep(i,l,r) for(int i = (l); i < (r); i++)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define pb push_back
#define ss second
#define ff first
void err(istringstream *iss){}template<typename T,typename ...Args> void err(istringstream *iss,const T &_val, const Args&...args){string _name;*iss>>_name;if(_name.back()==',')_name.pop_back();cerr<<_name<<" = "<<_val<<", ",err(iss,args...);}
void IOS(){
cin.tie(0) -> sync_with_stdio(0);
#ifndef ONLINE_JUDGE
#define er(args ...) cerr << __LINE__ << ": ", err(new istringstream(string(#args)), args), cerr << endl
#else
#define er(args ...) 0
#endif
}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll mod = 1e9 + 7, maxn = 1e6 + 5, maxk = 2e2 + 5, p = 9973, lg = 22, inf = ll(1e18) + 5;
ll pw(ll a,ll b,ll md=mod){if(!b)return 1;ll k=pw(a,b>>1ll,md);return k*k%md*(b&1ll?a:1)%md;}
ll dp[maxn][4];
vector<pp> adj[maxn];
ll mx[maxn];
void dfs(int r, int p, int vl){
ll sum = 0;
ll mxx = -inf;
for(auto[c, w]: adj[r]) if(c - p){
dfs(c, r, w);
sum += dp[c][2];
mxx = max(mxx, dp[c][3] - dp[c][2] + w);
}
dp[r][3] = sum;
dp[r][2] = max(sum, sum + mxx + vl);
ll tmp = -inf;
for(auto[c, w]: adj[r]) if(c - p){
mx[c] = tmp;
tmp = max(tmp, dp[c][3] - dp[c][2] + w);
}
reverse(all(adj[r]));
tmp = -inf;
for(auto[c, w]: adj[r]) if(c - p){
mx[c] = max(mx[c], tmp);
dp[r][1] = max({dp[r][1], sum - dp[c][2] + dp[c][0], sum - dp[c][2] + mx[c] + dp[c][1] + w});
dp[r][0] = max(dp[r][0], vl + dp[c][1] + sum - dp[c][2] + w);
tmp = max(tmp, dp[c][3] - dp[c][2] + w);
}
dp[r][0] = max(dp[r][0], dp[r][1]);
// er(r, dp[r][0], dp[r][1], dp[r][2], dp[r][3]);
}
int main(){ IOS();
int n; cin >> n;
rep(i,1,n){
int u, v, w; cin >> u >> v >> w; u--, v--;
adj[u].pb({v, w});
adj[v].pb({u, w});
}
dfs(0, -1, 0);
cout << dp[0][1] << '\n';
return 0-0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
23832 KB |
Output is correct |
2 |
Correct |
17 ms |
23716 KB |
Output is correct |
3 |
Correct |
15 ms |
23824 KB |
Output is correct |
4 |
Correct |
14 ms |
23828 KB |
Output is correct |
5 |
Correct |
16 ms |
23828 KB |
Output is correct |
6 |
Correct |
16 ms |
23740 KB |
Output is correct |
7 |
Correct |
16 ms |
23828 KB |
Output is correct |
8 |
Correct |
15 ms |
23716 KB |
Output is correct |
9 |
Correct |
14 ms |
23884 KB |
Output is correct |
10 |
Correct |
14 ms |
23812 KB |
Output is correct |
11 |
Correct |
14 ms |
23828 KB |
Output is correct |
12 |
Correct |
13 ms |
23764 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
23832 KB |
Output is correct |
2 |
Correct |
17 ms |
23716 KB |
Output is correct |
3 |
Correct |
15 ms |
23824 KB |
Output is correct |
4 |
Correct |
14 ms |
23828 KB |
Output is correct |
5 |
Correct |
16 ms |
23828 KB |
Output is correct |
6 |
Correct |
16 ms |
23740 KB |
Output is correct |
7 |
Correct |
16 ms |
23828 KB |
Output is correct |
8 |
Correct |
15 ms |
23716 KB |
Output is correct |
9 |
Correct |
14 ms |
23884 KB |
Output is correct |
10 |
Correct |
14 ms |
23812 KB |
Output is correct |
11 |
Correct |
14 ms |
23828 KB |
Output is correct |
12 |
Correct |
13 ms |
23764 KB |
Output is correct |
13 |
Correct |
14 ms |
23764 KB |
Output is correct |
14 |
Correct |
14 ms |
23820 KB |
Output is correct |
15 |
Correct |
15 ms |
23828 KB |
Output is correct |
16 |
Correct |
16 ms |
23784 KB |
Output is correct |
17 |
Correct |
13 ms |
23832 KB |
Output is correct |
18 |
Correct |
14 ms |
23824 KB |
Output is correct |
19 |
Correct |
14 ms |
23844 KB |
Output is correct |
20 |
Correct |
15 ms |
23764 KB |
Output is correct |
21 |
Correct |
14 ms |
23764 KB |
Output is correct |
22 |
Correct |
14 ms |
23764 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
23832 KB |
Output is correct |
2 |
Correct |
17 ms |
23716 KB |
Output is correct |
3 |
Correct |
15 ms |
23824 KB |
Output is correct |
4 |
Correct |
14 ms |
23828 KB |
Output is correct |
5 |
Correct |
16 ms |
23828 KB |
Output is correct |
6 |
Correct |
16 ms |
23740 KB |
Output is correct |
7 |
Correct |
16 ms |
23828 KB |
Output is correct |
8 |
Correct |
15 ms |
23716 KB |
Output is correct |
9 |
Correct |
14 ms |
23884 KB |
Output is correct |
10 |
Correct |
14 ms |
23812 KB |
Output is correct |
11 |
Correct |
14 ms |
23828 KB |
Output is correct |
12 |
Correct |
13 ms |
23764 KB |
Output is correct |
13 |
Correct |
14 ms |
23764 KB |
Output is correct |
14 |
Correct |
14 ms |
23820 KB |
Output is correct |
15 |
Correct |
15 ms |
23828 KB |
Output is correct |
16 |
Correct |
16 ms |
23784 KB |
Output is correct |
17 |
Correct |
13 ms |
23832 KB |
Output is correct |
18 |
Correct |
14 ms |
23824 KB |
Output is correct |
19 |
Correct |
14 ms |
23844 KB |
Output is correct |
20 |
Correct |
15 ms |
23764 KB |
Output is correct |
21 |
Correct |
14 ms |
23764 KB |
Output is correct |
22 |
Correct |
14 ms |
23764 KB |
Output is correct |
23 |
Correct |
15 ms |
24312 KB |
Output is correct |
24 |
Correct |
16 ms |
24316 KB |
Output is correct |
25 |
Correct |
15 ms |
24344 KB |
Output is correct |
26 |
Correct |
17 ms |
24788 KB |
Output is correct |
27 |
Correct |
19 ms |
24860 KB |
Output is correct |
28 |
Correct |
19 ms |
24796 KB |
Output is correct |
29 |
Correct |
17 ms |
24788 KB |
Output is correct |
30 |
Correct |
20 ms |
24736 KB |
Output is correct |
31 |
Correct |
17 ms |
25248 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
23832 KB |
Output is correct |
2 |
Correct |
17 ms |
23716 KB |
Output is correct |
3 |
Correct |
15 ms |
23824 KB |
Output is correct |
4 |
Correct |
14 ms |
23828 KB |
Output is correct |
5 |
Correct |
16 ms |
23828 KB |
Output is correct |
6 |
Correct |
16 ms |
23740 KB |
Output is correct |
7 |
Correct |
16 ms |
23828 KB |
Output is correct |
8 |
Correct |
15 ms |
23716 KB |
Output is correct |
9 |
Correct |
14 ms |
23884 KB |
Output is correct |
10 |
Correct |
14 ms |
23812 KB |
Output is correct |
11 |
Correct |
14 ms |
23828 KB |
Output is correct |
12 |
Correct |
13 ms |
23764 KB |
Output is correct |
13 |
Correct |
14 ms |
23764 KB |
Output is correct |
14 |
Correct |
14 ms |
23820 KB |
Output is correct |
15 |
Correct |
15 ms |
23828 KB |
Output is correct |
16 |
Correct |
16 ms |
23784 KB |
Output is correct |
17 |
Correct |
13 ms |
23832 KB |
Output is correct |
18 |
Correct |
14 ms |
23824 KB |
Output is correct |
19 |
Correct |
14 ms |
23844 KB |
Output is correct |
20 |
Correct |
15 ms |
23764 KB |
Output is correct |
21 |
Correct |
14 ms |
23764 KB |
Output is correct |
22 |
Correct |
14 ms |
23764 KB |
Output is correct |
23 |
Correct |
15 ms |
24312 KB |
Output is correct |
24 |
Correct |
16 ms |
24316 KB |
Output is correct |
25 |
Correct |
15 ms |
24344 KB |
Output is correct |
26 |
Correct |
17 ms |
24788 KB |
Output is correct |
27 |
Correct |
19 ms |
24860 KB |
Output is correct |
28 |
Correct |
19 ms |
24796 KB |
Output is correct |
29 |
Correct |
17 ms |
24788 KB |
Output is correct |
30 |
Correct |
20 ms |
24736 KB |
Output is correct |
31 |
Correct |
17 ms |
25248 KB |
Output is correct |
32 |
Correct |
48 ms |
29096 KB |
Output is correct |
33 |
Correct |
53 ms |
29144 KB |
Output is correct |
34 |
Correct |
38 ms |
28984 KB |
Output is correct |
35 |
Correct |
178 ms |
43964 KB |
Output is correct |
36 |
Correct |
184 ms |
43964 KB |
Output is correct |
37 |
Correct |
183 ms |
44088 KB |
Output is correct |
38 |
Correct |
126 ms |
43092 KB |
Output is correct |
39 |
Correct |
118 ms |
43052 KB |
Output is correct |
40 |
Correct |
131 ms |
43008 KB |
Output is correct |
41 |
Correct |
157 ms |
48420 KB |
Output is correct |