#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44
/*const int MOD = ;
inline int lgput(int a, int b) {
int ans = 1;
while(b > 0) {
if(b & 1) ans = (1LL * ans * a) % MOD;
b >>= 1;
a = (1LL * a * a) % MOD;
}
return ans;
}
inline void mod(int &x) {
if(x >= MOD)
x -= MOD;
}
inline void add(int &x, int y) {
x += y;
mod(x);
}
inline void sub(int &x, int y) {
x += MOD - y;
mod(x);
}
inline void mul(int &x, int y) {
x = (1LL * x * y) % MOD;
}*/
using namespace std;
const int INF = 2e9;
const int MAXN = (int) 2e5;
vector < pair <int, int> > g[MAXN + 1];
int dp[MAXN + 1][2];
void dfs(int nod, int par) {
vector <int> cur(3, -INF);
cur[0] = 0;
for(auto it : g[nod]) {
if(it.first != par) {
dfs(it.first, nod);
int mx = max(dp[it.first][1] + it.second, dp[it.first][0]);
vector <int> aux(3, -INF);
aux[0] = cur[0] + mx;
aux[1] = max(cur[0] + dp[it.first][0] + it.second, cur[1] + mx);
aux[2] = max(cur[1] + dp[it.first][0] + it.second, cur[2] + mx);
swap(cur, aux);
}
}
dp[nod][0] = max(cur[0], cur[2]);
dp[nod][1] = cur[1];
}
int main() {
//ifstream cin("A.in");
//ofstream cout("A.out");
int i, n;
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
cin >> n;
for(i = 1; i < n; i++) {
int x, y, z;
cin >> x >> y >> z;
g[x].push_back({y, z});
g[y].push_back({x, z});
}
dfs(1, 0);
cout << dp[1][0];
//cin.close();
//cout.close();
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
5240 KB |
Output is correct |
2 |
Correct |
6 ms |
4984 KB |
Output is correct |
3 |
Correct |
6 ms |
4984 KB |
Output is correct |
4 |
Correct |
6 ms |
5112 KB |
Output is correct |
5 |
Correct |
6 ms |
5112 KB |
Output is correct |
6 |
Incorrect |
6 ms |
5112 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
5240 KB |
Output is correct |
2 |
Correct |
6 ms |
4984 KB |
Output is correct |
3 |
Correct |
6 ms |
4984 KB |
Output is correct |
4 |
Correct |
6 ms |
5112 KB |
Output is correct |
5 |
Correct |
6 ms |
5112 KB |
Output is correct |
6 |
Incorrect |
6 ms |
5112 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
5240 KB |
Output is correct |
2 |
Correct |
6 ms |
4984 KB |
Output is correct |
3 |
Correct |
6 ms |
4984 KB |
Output is correct |
4 |
Correct |
6 ms |
5112 KB |
Output is correct |
5 |
Correct |
6 ms |
5112 KB |
Output is correct |
6 |
Incorrect |
6 ms |
5112 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
5240 KB |
Output is correct |
2 |
Correct |
6 ms |
4984 KB |
Output is correct |
3 |
Correct |
6 ms |
4984 KB |
Output is correct |
4 |
Correct |
6 ms |
5112 KB |
Output is correct |
5 |
Correct |
6 ms |
5112 KB |
Output is correct |
6 |
Incorrect |
6 ms |
5112 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |