Submission #930037

#	Time	Username	Problem	Language	Result	Execution time	Memory
930037		pan	Rigged Roads (NOI19_riggedroads)	C++17	37 / 100	319 ms	262144 KiB

riggedroads

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//#include "bits_stdc++.h"
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define lb lower_bound
#define ub upper_bound
#define input(x) scanf("%lld", &x);
#define input2(x, y) scanf("%lld%lld", &x, &y);
#define input3(x, y, z) scanf("%lld%lld%lld", &x, &y, &z);
#define input4(x, y, z, a) scanf("%lld%lld%lld%lld", &x, &y, &z, &a);
#define print(x, y) printf("%lld%c", x, y);
#define show(x) cerr << #x << " is " << x << endl;
#define show2(x,y) cerr << #x << " is " << x << " " << #y << " is " << y << endl;
#define show3(x,y,z) cerr << #x << " is " << x << " " << #y << " is " << y << " " << #z << " is " << z << endl;
#define discretize(x) sort(x.begin(), x.end()); x.erase(unique(x.begin(), x.end()), x.end());
using namespace std;
//using namespace __gnu_pbds;
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define ordered_multiset tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update>
typedef long long ll;
typedef long double ld;
typedef pair<ld, ll> pd;
typedef pair<string, ll> psl;
typedef pair<ll, ll> pi;
typedef pair<ll, pi> pii;
ll const MAXN = 3e5+5;
ll n, m, x;
vector<pi> edges;
bool mst[MAXN];
vector<pi> adj[MAXN];
vector<ll> cost;
// LCA
int lg(unsigned long long i) {
    return i ? __builtin_clzll(1) - __builtin_clzll(i) : -1;
}
ll label;
ll k, maxr;
vector<vector<pi > >rmq;
ll fa[MAXN],depth[MAXN], par[MAXN], ppath[MAXN];
vector<pi> arr;

void dfs(ll p, ll node) // euler path
{
	label++;
	fa[node] = label;
	arr.pb(mp(depth[node], node));
	for (pi u: adj[node])
	{
		if (u.f==p) continue;
		par[u.f] = node;
		ppath[u.f] = u.s;
		depth[u.f] = depth[node]+1;
		dfs(node, u.f);
		label++;
		arr.pb(mp(depth[node], node));
	}

}

void initrmq()
{
	maxr = arr.size();
	k = lg(maxr);
	rmq.assign(k+5, vector<pi> (maxr));
	rmq[0] = arr;
	for (ll i=1; i<=k; ++i)
	{
		for (ll j=0; j+ (1<<i) < maxr; ++j)
		{
			if (rmq[i-1][j].f < rmq[i-1][j + (1 << (i - 1))].f)
			{
				rmq[i][j] = rmq[i-1][j];
			}
			else
			{
				rmq[i][j] = rmq[i-1][j + (1 << (i - 1))];
			}
			
		}
	}
}

ll lca(ll node1, ll node2)
{
	ll l = fa[node1], r = fa[node2];
	if (l>r) swap(l,r);
	ll i = lg(r-l+1);
	if (rmq[i][l] < rmq[i][r - (1 << i) + 1])
	{
		return rmq[i][l].s;
	}
	else
	{
		return rmq[i][r - (1 << i) + 1].s;
	}
}

// UFDS
vector<ll> link1;
ll find(ll x)
{
	if (link1[x]!=x) link1[x] = find(link1[x]);
	return link1[x];
}
void unite(ll x, ll y)
{
	x = find(x), y = find(y);
	if (depth[x]>depth[y]) swap(x,y);
	link1[y] = link1[x];
}
// general
vector<ll> tobeset;
void update(ll from, ll until)
{
	from = find(from), until = find(until);
	ll counter = 0;
	while (from!=until)
	{
		counter++;
		tobeset.pb(ppath[from]);
		unite(from, par[from]);
		from = find(from), until = find(until);
		assert(counter<=3e5+5);
	}
}
int main()
{
	input2(n, m);
	link1.resize(n);
	edges.resize(m);
	cost.assign(m, -1);
	for (ll i=0; i<m; ++i) {input2(edges[i].f, edges[i].s); mst[i] = false; edges[i].f--; edges[i].s--;}
	for (ll i=0; i<n-1; ++i) 
	{
	    input(x); 
		x--;
		mst[x] = true;
		adj[edges[x].f].pb(mp(edges[x].s, x));
		adj[edges[x].s].pb(mp(edges[x].f, x));
	}
	label = -1;
	depth[0] = 0;
	dfs(-1, 0);
	initrmq();
	for (ll i=0; i<n; ++i) link1[i] = i;
	label = 0;
	for (ll i=0; i<m; ++i)
	{
		if (cost[i]!=-1) continue;
		if (mst[i]) {cost[i] = ++label; unite(edges[i].f, edges[i].s); continue;}
		ll lcanow = lca(edges[i].f, edges[i].s);
		tobeset.resize(0);
		update(edges[i].f, lcanow);
		update(edges[i].s, lcanow);
		sort(tobeset.begin(), tobeset.end());
		for (ll j=0; j<tobeset.size(); ++j) {cost[tobeset[j]] = ++label;}
		cost[i] = ++label;
	}
	for (ll i=0; i<m; ++i) print(cost[i], ' ');
	
	
	
	return 0;
}

Compilation message (stderr)

riggedroads.cpp: In function 'int main()':
riggedroads.cpp:160:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  160 |   for (ll j=0; j<tobeset.size(); ++j) {cost[tobeset[j]] = ++label;}
      |                ~^~~~~~~~~~~~~~~
riggedroads.cpp:12:27: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 | #define input2(x, y) scanf("%lld%lld", &x, &y);
      |                      ~~~~~^~~~~~~~~~~~~~~~~~~~
riggedroads.cpp:132:2: note: in expansion of macro 'input2'
  132 |  input2(n, m);
      |  ^~~~~~
riggedroads.cpp:12:27: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 | #define input2(x, y) scanf("%lld%lld", &x, &y);
      |                      ~~~~~^~~~~~~~~~~~~~~~~~~~
riggedroads.cpp:136:26: note: in expansion of macro 'input2'
  136 |  for (ll i=0; i<m; ++i) {input2(edges[i].f, edges[i].s); mst[i] = false; edges[i].f--; edges[i].s--;}
      |                          ^~~~~~
riggedroads.cpp:11:23: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | #define input(x) scanf("%lld", &x);
      |                  ~~~~~^~~~~~~~~~~~
riggedroads.cpp:139:6: note: in expansion of macro 'input'
  139 |      input(x);
      |      ^~~~~

• Subtask 1: 8 / 8
• Subtask 2: 19 / 19
• Subtask 3: 0 / 9
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 12
• Subtask 7: 0 / 32