#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;
}
int cnt[SZ];
void dfs(int u, int p, int t, int d, int minn){
//t == 0: calculate
//t == 1: add
//t == 2: delete
if (t == 0){
minn = min(minn, d);
//if (u == 4 && p == 2) cerr << d << " " << minn << "\n";
if (minn == d){
res += cnt[-minn];
}
}
if (t == 1){
minn = min(minn + a[u], a[u]);
if (minn >= 0) ++cnt[d];
}
if (t == 2){
minn = min(minn + a[u], a[u]);
if (minn >= 0) --cnt[d];
}
for (int i: adj[u]){
if (i == p || del[i]) continue;
dfs(i, u, t, d + a[i], minn);
}
}
void updateRes(int root)
{
if(a[root] == 1) cnt[1] = 1;
for(int u : adj[root])
{
if(del[u]) continue;
dfs(u, root, 0, a[u], 0);
dfs(u, root, 1, a[root] + a[u], a[root]);
}
for(int u : adj[root])
{
if(del[u]) continue;
dfs(u, root, 2, a[root] + a[u], a[root]);
}
if (a[root] == 1) cnt[1] = 0;
}
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:104:8: warning: unused variable 'preres' [-Wunused-variable]
104 | ll preres = res;
| ^~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
7772 KB |
Output is correct |
2 |
Correct |
14 ms |
7832 KB |
Output is correct |
3 |
Correct |
15 ms |
7832 KB |
Output is correct |
4 |
Correct |
12 ms |
7864 KB |
Output is correct |
5 |
Correct |
12 ms |
7768 KB |
Output is correct |
6 |
Correct |
14 ms |
7864 KB |
Output is correct |
7 |
Correct |
12 ms |
7772 KB |
Output is correct |
8 |
Correct |
15 ms |
7868 KB |
Output is correct |
9 |
Correct |
12 ms |
8024 KB |
Output is correct |
10 |
Correct |
7 ms |
7772 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
3104 ms |
46008 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
7772 KB |
Output is correct |
2 |
Correct |
14 ms |
7832 KB |
Output is correct |
3 |
Correct |
15 ms |
7832 KB |
Output is correct |
4 |
Correct |
12 ms |
7864 KB |
Output is correct |
5 |
Correct |
12 ms |
7768 KB |
Output is correct |
6 |
Correct |
14 ms |
7864 KB |
Output is correct |
7 |
Correct |
12 ms |
7772 KB |
Output is correct |
8 |
Correct |
15 ms |
7868 KB |
Output is correct |
9 |
Correct |
12 ms |
8024 KB |
Output is correct |
10 |
Correct |
7 ms |
7772 KB |
Output is correct |
11 |
Execution timed out |
3104 ms |
46008 KB |
Time limit exceeded |
12 |
Halted |
0 ms |
0 KB |
- |