#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define ull unsigned long long
#define pii pair<int,int>
#define pll pair<long long, long long>
#define fi first
#define se second
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define lwb lower_bound
#define upb upper_bound
#define TASKNAME "NAME"
void init()
{
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
///freopen(TASKNAME".INP","r",stdin); freopen(TASKNAME".OUT","w",stdout);
}
const int SZ = 3e5+5;
const ll INF = INT_MAX / 2, MOD = 1e9+7, INFLL = 2e18;
const double epsilon = 1e-3;
int n, a[SZ];
string s;
vector<int> adj[SZ];
ll res = 0;
bool del[SZ];
void dfsSize(int u, int pre)
{
s[u] = 1;
for(int v : adj[u])
{
if(v == pre || del[v]) continue;
dfsSize(v,u);
s[u] += s[v];
}
}
int findCentroid(int u, int pre, int treeSize)
{
for(int v : adj[u])
{
if(v == pre || del[v]) continue;
if(s[v] > treeSize / 2) return findCentroid(v, u, treeSize);
}
return u;
}
map<int, int> cnt;
void dfs(int u, int pre, int sum, int mn1, int mn2, int type)
{
if(type == 1)
{
if(mn2 >= 0) cnt[sum]++;
}
if(type == 2)
{
if(mn1 == sum && sum <= 0)
{
res += 1LL * cnt[-sum];
}
if(sum == 0)
{
if(mn1 >= 0) res++;
//if(mn1 >= 0 && root == 2) cout << "a\n";
}
}
if(type == 3)
{
if(mn2 >= 0) cnt[sum]--;
}
for(int v : adj[u])
{
if(del[v] || v == pre) continue;
dfs(v, u, sum + a[v], min(mn1, sum + a[v]), min(a[v], a[v] + mn2), type);
}
}
void updateRes(int root)
{
for(int u : adj[root])
{
if(del[u]) continue;
dfs(u, root, a[root] + a[u], min(a[root], a[root] + a[u]), min(a[u], a[u] + a[root]) , 2);
dfs(u, root, a[u], min(a[root], a[root] + a[u]), min(a[u], a[u] + a[root]) , 1);
}
for(int u : adj[root])
{
if(del[u]) continue;
dfs(u, root, a[u], min(a[root], a[root] + a[u]), min(a[u], a[u] + a[root]) , 3);
}
}
void solve(int u)
{
dfsSize(u,0);
int root = findCentroid(u, 0, s[u]);
del[root] = true;
ll preres = res;
updateRes(root);
//cout << root << " - " << res - preres << '\n';
for(int v : adj[root])
{
if(del[v]) continue;
solve(v);
}
}
int main()
{
init();
cin >> n;
cin >> s;
s = " " + s;
for(int i = 1; i <= n; i++)
{
if(s[i] == '(') a[i] = 1;
else a[i] = -1;
}
for(int i = 1; i < n; i++)
{
int u,v;
cin >> u >> v;
adj[u].pb(v);
adj[v].pb(u);
}
solve(1);
for(int i = 1; i <= n; i++)
{
if(a[i] == 1) a[i] = -1;
else a[i] = 1;
}
memset(del, false, sizeof(del));
solve(1);
cout << res;
}
Compilation message
zagrade.cpp: In function 'void solve(int)':
zagrade.cpp:106:8: warning: unused variable 'preres' [-Wunused-variable]
106 | ll preres = res;
| ^~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
8792 KB |
Output is correct |
2 |
Correct |
16 ms |
8892 KB |
Output is correct |
3 |
Correct |
20 ms |
8792 KB |
Output is correct |
4 |
Correct |
14 ms |
8812 KB |
Output is correct |
5 |
Correct |
16 ms |
8892 KB |
Output is correct |
6 |
Correct |
20 ms |
8864 KB |
Output is correct |
7 |
Correct |
16 ms |
8892 KB |
Output is correct |
8 |
Correct |
22 ms |
8796 KB |
Output is correct |
9 |
Correct |
16 ms |
8892 KB |
Output is correct |
10 |
Correct |
9 ms |
8796 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
3011 ms |
48824 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
8792 KB |
Output is correct |
2 |
Correct |
16 ms |
8892 KB |
Output is correct |
3 |
Correct |
20 ms |
8792 KB |
Output is correct |
4 |
Correct |
14 ms |
8812 KB |
Output is correct |
5 |
Correct |
16 ms |
8892 KB |
Output is correct |
6 |
Correct |
20 ms |
8864 KB |
Output is correct |
7 |
Correct |
16 ms |
8892 KB |
Output is correct |
8 |
Correct |
22 ms |
8796 KB |
Output is correct |
9 |
Correct |
16 ms |
8892 KB |
Output is correct |
10 |
Correct |
9 ms |
8796 KB |
Output is correct |
11 |
Execution timed out |
3011 ms |
48824 KB |
Time limit exceeded |
12 |
Halted |
0 ms |
0 KB |
- |