This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
//#define int ll
const int inf = int(1e9);
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> p2;
#define rep(i, high) for (int i = 0; i < high; i++)
#define repp(i, low, high) for (int i = low; i < high; i++)
#define repe(i, container) for (auto& i : container)
#define sz(container) ((int)container.size())
#define all(x) begin(x),end(x)
#define ceildiv(x,y) ((x + y - 1) / (y))
inline void fast() { ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); }
#define _LOCAL _DEBUG
#if _LOCAL
#define assert(x) if (!(x)) __debugbreak()
#endif
const int maxn = int(1.5e5);
int tin[maxn];
int tout[maxn];
int timer = 0;
int up[maxn][18];
bool upincreasing[maxn][18];
bool updecreasing[maxn][18];
int upmax[maxn][18];
int upmin[maxn][18];
int upv[maxn];
int depth[maxn];
int cnt[maxn];
void dfs(int u, int p, int p1, int _p2, vector<vector<p2>>& edges)
{
depth[u] = depth[p] + 1;
tin[u] = timer++;
up[u][0] = p;
upmax[u][0] = upv[u];
upmin[u][0] = upv[u];
upincreasing[u][0] = upmax[u][0] < upmax[p][0] || p==0 || u==0;
updecreasing[u][0] = upmax[u][0] > upmax[p][0] || p==0 || u==0;
repp(d,1,18)
{
int mid = up[u][d - 1];
up[u][d] = up[mid][d - 1];
upmax[u][d] = max(upmax[u][d - 1], upmax[mid][d - 1]);
upmin[u][d] = min(upmin[u][d - 1], upmin[mid][d - 1]);
upincreasing[u][d] = upincreasing[u][d - 1] && upincreasing[mid][d - 1] && (upmax[mid][0] < upmax[up[mid][0]][0] || up[mid][0] ==0||mid==0);
updecreasing[u][d] = updecreasing[u][d - 1] && updecreasing[mid][d - 1] && (upmax[mid][0] > upmax[up[mid][0]][0] || up[mid][0] ==0||mid==0);
}
repe(e, edges[u]) if (e.first != p)
{
upv[e.first] = e.second;
dfs(e.first, u, p1, _p2, edges);
}
tout[u] = timer++;
}
bool isancestor(int a, int b)
{
return tin[a] <= tin[b] && tout[a] >= tout[b];
}
int pathmax(int a, int b)
{
if (isancestor(a, b)) return -1;
int ret = -1;
for (int d = 17; d >= 0; d--)
{
if (!isancestor(up[a][d], b))
{
ret = max(ret, upmax[a][d]);
a = up[a][d];
}
}
return max(ret, upmax[a][0]);
}
int pathmin(int a, int b)
{
if (isancestor(a, b)) return inf;
int ret = inf;
for (int d = 17; d >= 0; d--)
{
if (!isancestor(up[a][d], b))
{
ret = min(ret, upmin[a][d]);
a = up[a][d];
}
}
return min(ret, upmin[a][0]);
}
int lca(int a, int b)
{
if (isancestor(a, b)) return a;
if (isancestor(b, a)) return b;
for (int d = 17; d >= 0; d--)
{
if (!isancestor(up[a][d],b))
{
a = up[a][d];
}
}
return up[a][0];
}
struct Centroid
{
int n;
vvi edges;
vi vis;
vi par;
vi size;
Centroid() {}
Centroid(vvi& edges) : edges(edges), n(edges.size()), vis(n), par(n), size(n)
{
init_centroid(0, -1);
}
int find_centroid(int u, int p, int n)
{
repe(e, edges[u])
{
if (e == p) continue;
if (!vis[e] && size[e] > n / 2) return find_centroid(e, u, n);
}
return u;
}
int find_size(int u, int p)
{
if (vis[u]) return 0;
size[u] = 1;
repe(e, edges[u])
{
if (e == p) continue;
size[u] += find_size(e, u);
}
return size[u];
}
void init_centroid(int u, int p)
{
find_size(u, u);
int c = find_centroid(u, u, size[u]);
vis[c] = 1;
par[c] = p;
repe(e, edges[c])
{
if (!vis[e]) init_centroid(e, c);
}
}
};
int cdepth[maxn];
void d(int u, int p, vvi& adj)
{
cdepth[u] = cdepth[p] + 1;
repe(e, adj[u]) if (e != p) d(e, u, adj);
}
signed main()
{
fast();
//ifstream in("C:\\Users\\Matis\\desktop\\comp_prog\\x64\\debug\\in.txt");
//cin.rdbuf(in.rdbuf());
int n, q;
cin >> n >> q;
vvi queries;
int t = 0;
vector<vector<p2>> edges(n);
vector<p2> edgelist;
vvi e(n);
rep(i, n + q - 1)
{
char c;
cin >> c;
if (c=='S')
{
int a, b;
cin >> a >> b;
a--; b--;
edgelist.push_back(p2(a, b));
edges[a].push_back(p2(b, t));
edges[b].push_back(p2(a, t));
e[a].push_back(b);
e[b].push_back(a);
t++;
}
else if (c=='Q')
{
int a, b;
cin >> a >> b;
a--; b--;
queries.push_back({ 0, b, a, t-1 });
}
else
{
int c;
cin >> c;
c--;
queries.push_back({ 1, c, -1, t-1 });
}
}
depth[0] = 0;
dfs(0, 0, -1, -1, edges);
Centroid cent(e);
auto getmax = [&](int a, int b)
{
return max(pathmax(a, b), pathmax(b, a));
};
auto getmin = [&](int a, int b)
{
return min(pathmin(a, b), pathmin(b, a));
};
auto pathgood = [&](int a, int b, int t)
{
if (getmax(a, b) > t) return false;
// all edges <= t
// from b->lca increasing
// from a->lca decreasing
bool good = 1;
int u = b;
int prev = inf;
for (int d = 17; d >= 0; d--)
{
if (!isancestor(up[u][d],a))
{
good &= updecreasing[u][d];
u = up[u][d];
}
}
if (!isancestor(u,a))
{
prev = upmax[u][0];
}
u = a;
int v = -1;
for (int d = 17; d >= 0; d--)
{
if (!isancestor(up[u][d], b))
{
good &= upincreasing[u][d];
u = up[u][d];
}
}
if (!isancestor(u, b))
{
v = upmax[u][0];
}
return good && (v < prev);
};
vector<map<int,int>> children(n);
vi sum(n);
vvi blocked(n);
rep(i, n)blocked[i].push_back(inf);
vi parenton(n);
vi centroidpar = cent.par;
vvi centroidadj(n);
rep(i, n)
{
if (centroidpar[i] == -1) continue;
centroidadj[i].push_back(centroidpar[i]);
centroidadj[centroidpar[i]].push_back(i);
}
Centroid c2(e);
c2.vis = vi(n); c2.par = vi(n); c2.size = vi(n);
c2.find_size(0, 0);
int center = c2.find_centroid(0, 0, c2.size[0]);
d(center, center, centroidadj);
auto enable = [&](int ind)
{
int u = cdepth[edgelist[ind].first] > cdepth[edgelist[ind].second] ? edgelist[ind].first : edgelist[ind].second;
int s = u;
while (true)
{
if (!pathgood(s,u,ind)) break;
if (centroidpar[u] == -1) break;
int pe = getmin(u, centroidpar[u]);
repe(c, blocked[u])
{
if (c>pe)
{
children[centroidpar[u]][pe]++;
blocked[centroidpar[u]].push_back(pe);
}
}
blocked[u] = vi();
u = centroidpar[u];
}
};
int timer = 0;
repe(q, queries)
{
int type=q[0], a=q[1], b=q[2], t=q[3];
if (type==0)
{
cout << (pathgood(a, b, t) ? "yes" : "no") << "\n";
}
else
{
while (timer<=t)
{
enable(timer++);
}
int ans = 0;
repe(c, children[a]) ans += c.second;
int u=a;
int prev = u;
while (u!=center)
{
prev = u;
u = centroidpar[u];
if (!pathgood(a, u, t)) break;
ans+=depth[u]+depth[prev]-2*depth[lca(u,prev)];
int v = getmin(a, u);
repe(c, children[u]) if (c.first > v) ans += c.second;
if (u == 0)
{
break;
}
}
cout << ans+1 << "\n";
}
}
return 0;
}
Compilation message (stderr)
servers.cpp: In constructor 'Centroid::Centroid(vvi&)':
servers.cpp:120:6: warning: 'Centroid::edges' will be initialized after [-Wreorder]
120 | vvi edges;
| ^~~~~
servers.cpp:119:6: warning: 'int Centroid::n' [-Wreorder]
119 | int n;
| ^
servers.cpp:126:2: warning: when initialized here [-Wreorder]
126 | Centroid(vvi& edges) : edges(edges), n(edges.size()), vis(n), par(n), size(n)
| ^~~~~~~~
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |