oj.uz

Submission #387845

# Submission time Handle Problem Language Result Execution time Memory
387845 2021-04-09T09:35:17 Z AmShZ Swapping Cities (APIO20_swap) C++11
0 / 100
 343 ms 61508 KB 
// khodaya khodet komak kon
# include <bits/stdc++.h>
 
/*
// ordered_set 
# include <ext/pb_ds/assoc_container.hpp>
# include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
# define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> 
*/
 
using namespace std;
 
typedef long long                                        ll;
typedef long double                                      ld;
typedef pair <int, int>                                  pii;
typedef pair <ll, ll>                                    pll;
typedef pair <pll,  ll>                                  ppi;
typedef pair <int, pii>                                  pip;
typedef pair <pii, pii>                                  ppp;
 
# define A                                               first
# define B                                               second
# define endl                                            '\n'
# define sep                                             ' '
# define all(x)                                          x.begin(), x.end()
# define kill(x)                                         return cout << x << endl, 0
# define SZ(x)                                           int(x.size())
# define lc                                              id << 1
# define rc                                              id << 1 | 1
# define InTheNameOfGod                                  ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
 
ll power(ll a, ll b, ll md) {return (!b ? 1 : (b & 1 ? a * power(a * a % md, b / 2, md) % md : power(a * a % md, b / 2, md) % md));}
 
const int xn = 2e5 + 10;
const int xm = 10 + 10;
const int sq = 320;
const int inf = 1e9 + 10;
const ll INF = 1e18 + 10;
const int mod = 1e9 + 7;//998244353;
const int base = 257;

int dsu[xn], sz[xn], par[xm][xn];
int H[xn], mn[xn], a[xn];
pii mx[xm][xn];
bool inmst[xn];
set <pii> st[xn], ts[xn];
vector <pip> E;
vector <pii> adj[xn], G[xn];

int get_root(int v){
	if (v == dsu[v])
		return v;
	return dsu[v] = get_root(dsu[v]);
}
void preDFS(int v){
	for (int i = 1; i < xm; ++ i){
		par[i][v] = par[i - 1][v];
		mx[i][v].A = max(mx[i - 1][v].A, mx[i - 1][par[i - 1][v]].A);
		mx[i][v].B = max(mx[i - 1][v].B, mx[i - 1][par[i - 1][v]].B);
	}
	for (pii u : adj[v]){
		if (u.A == par[0][v])
			continue;
		par[0][u.A] = v;
		mx[0][u.A] = {E[u.B].A, mn[v]};
		H[u.A] = H[v] + 1;
		preDFS(u.A);
	}
}
int LCA(int v, int u){
	if (H[v] > H[u])
		swap(v, u);
	for (int i = xm - 1; i >= 0; -- i)
		if ((1 << i) <= H[u] - H[v])
			u = par[i][u];
	if (v == u)
		return v;
	for (int i = xm - 1; i >= 0; -- i)
		if (par[i][v] != par[i][u])
			v = par[i][v], u = par[i][u];
	return par[0][v];
}
void merge(int v, int u){
	v = get_root(v);
	u = get_root(u);
	if (sz[v] < sz[u])
		swap(v, u);
	dsu[u] = v, sz[v] += sz[u];
	for (pii x : st[u])
		st[v].insert(x);
}
void DFS(int v){
	for (pii u : adj[v])
		if (u.A != par[0][v])
			DFS(u.A), merge(v, u.A);
	for (pii u : G[v]){
		int lca = LCA(v, u.A);
		st[v].insert({E[u.B].A, u.B});
		ts[lca].insert({E[u.B].A, u.B});
	}
	for (pii x : ts[v])
		st[v].erase(x);
	a[v] = inf;
	if (SZ(st[v]))
		a[v] = st[v].begin() -> A;
}
void init(int n, int m, vector <int> V, vector <int> U, vector <int> W){
	for (int i = 1; i <= n; ++ i)
		dsu[i] = i, sz[i] = 1;
	for (int i = 0; i < m; ++ i){
		int v = V[i] + 1, u = U[i] + 1, w = W[i];
		E.push_back({w, {v, u}});
	}
	sort(all(E));
	for (int i = 0; i < m; ++ i){
		pip e = E[i];
		int v = e.B.A, u = e.B.B, w = e.A;
		int pv = v, pu = u;
		v = get_root(v);
		u = get_root(u);
		if (v == u){
			G[pv].push_back({pu, i});
			G[pu].push_back({pv, i});
			continue;
		}
		if (sz[v] < sz[u])
			swap(v, u);
		inmst[i] = true;
		dsu[u] = v, sz[v] += sz[u];
		adj[pv].push_back({pu, i});
		adj[pu].push_back({pv, i});
	}
	for (int i = 1; i <= n; ++ i){
		dsu[i] = i, sz[i] = 1;
		mn[i] = inf;
		for (pii u : G[i])
			mn[i] = min(mn[i], E[u.B].A);
	}
	preDFS(1), DFS(1);
}
int getMinimumFuelCapacity(int v, int u){
	++ v, ++ u;
	int lca = LCA(v, u), res = inf, ans = 0;
	int pv = v, pu = u;
	if (H[v] > H[u])
		swap(v, u);
	for (int i = xm - 1; i >= 0; -- i){
		if (H[u] - H[v] < (1 << i))
			continue;
		ans = max(ans, mx[i][u].A);
		res = min(res, mx[i][u].B);
		u = par[i][u];
	}
	for (int i = xm - 1; i >= 0; -- i){
		if (par[i][v] == par[i][u])
			continue;
		ans = max(ans, mx[i][v].A);
		res = min(res, mx[i][v].B);
		ans = max(ans, mx[i][u].A);
		res = min(res, mx[i][u].B);
		v = par[i][v], u = par[i][u];
	}
	if (v != u){
		ans = max(ans, mx[0][v].A);
		res = min(res, mx[0][v].B);
		ans = max(ans, mx[0][u].A);
		res = min(res, mx[0][u].B);
	}
	v = pv, u = pu;
	res = min(res, min(a[v], a[u]));
	if (res == inf)
		return - 1;
	return max(ans, res);
}

/*
int n, m, q;
vector <int> V, U, W;

int main(){
	InTheNameOfGod;

	cin >> n >> m;
	for (int i = 0; i < m; ++ i){
		int v, u, w;
		cin >> v >> u >> w;
		V.push_back(v);
		U.push_back(u);
		W.push_back(w);
	}
	init(n, m, V, U, W);
	cin >> q;
	while (q --){
		int v, u;
		cin >> v >> u;
		cout << getMinimumFuelCapacity(v, u) << endl;
	}
		
	return 0;
}

5 6
0 1 4
0 2 4
1 4 10
1 3 2
1 2 1
2 3 3
3
1 2
2 4
0 1
*/

Compilation message

swap.cpp: In function 'void init(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
swap.cpp:118:29: warning: unused variable 'w' [-Wunused-variable]
  118 |   int v = e.B.A, u = e.B.B, w = e.A;
      |                             ^
swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:144:6: warning: unused variable 'lca' [-Wunused-variable]
  144 |  int lca = LCA(v, u), res = inf, ans = 0;
      |      ^~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Correct 17 ms 28672 KB Output is correct
4 Incorrect 17 ms 28892 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Incorrect 343 ms 61508 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Correct 17 ms 28672 KB Output is correct
4 Incorrect 17 ms 28892 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Correct 17 ms 28672 KB Output is correct
4 Incorrect 17 ms 28892 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Correct 17 ms 28672 KB Output is correct
4 Incorrect 17 ms 28892 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 28748 KB Output is correct
2 Correct 17 ms 28748 KB Output is correct
3 Correct 17 ms 28672 KB Output is correct
4 Incorrect 17 ms 28892 KB Output isn't correct
5 Halted 0 ms 0 KB -