| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 235948 |
2020-05-30T13:00:12 Z |
Vimmer |
Usmjeri (COCI17_usmjeri) |
C++14 |
|
88 ms |
91272 KB |
#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("-O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("fast-math")
//#pragma GCC optimize("no-stack-protector")
#define F first
#define S second
#define sz(x) int(x.size())
#define pb push_back
#define N 300001
#define M ll(1e9 + 7)
#define inf 1e9 + 1e9
using namespace std;
//using namespace __gnu_pbds;
typedef long double ld;
typedef long long ll;
typedef short int si;
//typedef tree <int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
vector <array <int, 2> > g[N];
bool mkr[N];
int pr[N], rk[N], t[N + N][20], in[N], tin[N], tout[N], id, h[N], logs[N + N], mnr[N];
int fnd(int x) {if (pr[x] != x) pr[x] = fnd(pr[x]); return pr[x];}
void link(int x, int y)
{
if (rk[x] < rk[y]) swap(x, y);
pr[y] = x;
rk[x] += rk[y];
}
vector <int> path[N], vr, to[N], glub[N], lnk[N], a[N];
ll ans = 1;
array <int, 2> pred[N];
void dfser(int v, int p)
{
mkr[v] = 1;
for (auto it : path[v])
{
if (it == p) continue;
if (mkr[it]) {cout << 0 << endl; exit(0);}
dfser(it, v);
}
}
void spusk(int v, int p)
{
tin[v] = id++;
if (p != -1) h[v] = h[p] + 1; else pred[v] = {-1, -1};
glub[h[v]].pb(v);
in[v] = sz(vr);
vr.pb(v);
for (auto it : g[v])
{
if (it[0] == p) continue;
spusk(it[0], v);
pred[it[0]] = {v, it[1]};
vr.pb(v);
}
tout[v] = id++;
}
int lca(int a, int b)
{
if (in[a] > in[b]) swap(a, b);
int j = logs[in[b] - in[a] + 1];
a = t[in[a]][j];
b = t[in[b] - (1 << j) + 1][j];
if (h[a] > h[b]) return b;
return a;
}
int main()
{
freopen("input.txt", "r", stdin); //freopen("output4.txt", "w", stdout);
ios_base::sync_with_stdio(0); istream::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n, m;
cin >> n >> m;
for (int i = 2; i < N + N; i++) logs[i] = 1 + logs[i >> 1];
bool f = 1;
for (int i = 0; i < n - 1; i++)
{
int x, y;
cin >> x >> y;
g[x].pb({y, i});
g[y].pb({x, i});
pr[i] = i;
rk[i] = 1;
}
for (int i = 1; i <= n; i++) if (sz(g[i]) > 2) f = 0;
if (f)
{
int beg;
for (int i = 1; i <= n; i++) if (sz(g[i]) == 1) beg = i;
for (; m > 0 ; m--)
{
int x, y;
cin >> x >> y;
a[x].pb(m);
a[y].pb(m);
}
vector <int> vr; vr.clear();
int v = beg, p = -1;
while (v != -1)
{
int nxt = -1;
vr.pb(v);
for (auto it : g[v])
{
if (it[0] == p) continue;
nxt = it[0];
}
p = v;
v = nxt;
}
ll ans = 1;
set <int> se; se.clear();
for (int i = 0; i < sz(vr); i++)
{
bool f = 1;
if (i != 0 && sz(se) == 0) {f = 0; ans = (ans + ans) % M;}
for (auto it : a[vr[i]])
{
if (se.find(it) == se.end()) se.insert(it);
else se.erase(it);
}
if (i != 0 && f && sz(se) == 0) ans = (ans + ans) % M;
}
cout << ans << endl;
exit(0);
}
spusk(1, -1);
for (int i = 0; i < sz(vr); i++) t[i][0] = vr[i];
for (int j = 1; j < 20; j++)
for (int i = 0; i < sz(vr); i++)
{
int a = t[i][j - 1];
int b = t[min(sz(vr) - 1, i + (1 << (j - 1)))][j - 1];
if (h[a] > h[b]) t[i][j] = b; else t[i][j] = a;
}
for (int i = 1; i <= n; i++) mnr[i] = -1;
for (int i = 0; i < m; i++)
{
int x, y;
cin >> x >> y;
path[x].pb(y);
path[y].pb(x);
int lc = lca(x, y);
if (lc == x) to[y].pb(x);
else if (lc == y) to[x].pb(y);
else {to[x].pb(lc); to[y].pb(lc);}
}
// for (int i = 1; i <= n; i++)
// {
// if (mkr[i]) continue;
//
// dfser(i, -1);
// }
memset(mkr, 0, sizeof(mkr));
for (int i = N - 1; i >= 0; i--)
for (auto v : glub[i])
{
int root = -1;
if (sz(lnk[v]) != 0)
{
root = lnk[v][0];
for (auto it : lnk[v])
{
int x = fnd(root), y = fnd(it);
if (x != y) link(x, y);
}
}
int mn = -1;
for (auto it : to[v])
if (mn == -1 || h[mn] > h[it]) mn = it;
if (mnr[v] != -1 && (mn == -1 || h[mn] > h[mnr[v]])) mn = mnr[v];
if (mn == v || mn == -1) continue;
int nxt = pred[v][0], nm = pred[v][1];
if (nxt == -1) continue;
lnk[nxt].pb(nm);
if (mnr[nxt] == -1 || h[mnr[nxt]] > h[mn]) mnr[nxt] = mn;
if (mnr[v] != -1 && mnr[v] != v)
{
int x = fnd(root), y = fnd(nm);
if (x != y) link(x, y);
}
}
for (int i = 0; i < n - 1; i++)
{
int id = fnd(i);
if (mkr[id]) continue;
mkr[id] = 1;
ans = (ans + ans) % M;
}
cout << ans << endl;
}
Compilation message
usmjeri.cpp: In function 'int main()':
usmjeri.cpp:108:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
freopen("input.txt", "r", stdin); //freopen("output4.txt", "w", stdout);
~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
usmjeri.cpp:156:17: warning: 'beg' may be used uninitialized in this function [-Wmaybe-uninitialized]
int v = beg, p = -1;
^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
80 ms |
91000 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
87 ms |
91128 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
85 ms |
91128 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
82 ms |
91132 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
87 ms |
91036 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
88 ms |
91000 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
86 ms |
91272 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
80 ms |
91128 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
84 ms |
91004 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
85 ms |
91048 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
