oj.uz

Submission #1005122

# Submission time Handle Problem Language Result Execution time Memory
1005122 2024-06-22T07:33:33 Z vqpahmad One-Way Streets (CEOI17_oneway) C++14
100 / 100
 92 ms 23896 KB 
#include<bits/stdc++.h>
using namespace std;
#ifdef ONPC
#include"debug.h"
#else
#define debug(...) 42
#endif
#define endl '\n'
#define ll long long
#define pii pair<int,int>
#define F first
#define S second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
const int mod = 1e9 + 7;
const int MAXN = 1e5 + 15;
const int inf = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3f;
int n, m;
vector<pii> adj[MAXN];
int id[MAXN], fa[MAXN][20];
int dep[MAXN];
int dir[2][MAXN];
bool vis[MAXN];
void dfs1(int node, int par){
	debug(node, par);
	vis[node] = 1;
	fa[node][0] = par;
	dep[node] = dep[par] + 1;
	for (int b = 1; b < 20; b++){
		fa[node][b] = fa[fa[node][b - 1]][b - 1];
	}
	for (auto [to, idx] : adj[node]){
		if (idx == id[node]) continue;
		if (vis[to]) {
			if (dep[to] < dep[node]){
				debug(node, to, par, "!");
				dir[0][node] += 1;
				dir[0][to] -= 1;
				dir[1][node] += 1;
				dir[1][to] -= 1;
			}
		}
		else {
			id[to] = idx;
			dfs1(to, node);
		}
	}
}

void dfs3(int node){
	vis[node] = 1;
	for (auto [to, idx] : adj[node]){
		if (vis[to]) continue;
		dfs3(to);
		dir[0][node] += dir[0][to];
		dir[1][node] += dir[1][to];
	}
}
int LCA(int u, int v){
	if (dep[u] > dep[v]) swap(u, v);
	for (int b = 19; b >= 0; b--){
		if (dep[fa[v][b]] >= dep[u]) v = fa[v][b];
	}
	if (u == v) return u;
	for (int b = 19; b >= 0; b--){
		if (fa[u][b] != fa[v][b]){
			u = fa[u][b];
			v = fa[v][b];
		}
	}
	return fa[u][0];
}
int ans[MAXN];

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m;
	vector<pii> edges(m + 1);
	for (int i = 0; i < m; i++){
		int u, v;
		cin >> u >> v;
		edges[i + 1] = {u, v};
		adj[u].pb({v, i + 1});
		adj[v].pb({u, i + 1});
	}
	for (int i = 1; i <= n; i++){
		if (!vis[i]){
			dfs1(i, i);
		}
	}
	for (int i = 0; i <= n; i++){
		debug(i, dir[0][i], dir[1][i]);
	}
	debug("E");
	int q;
	cin >> q;
	while (q--){
		int u, v;
		cin >> u >> v;
		int lca = LCA(u, v);
		dir[0][u] += 1;
		dir[0][lca] -= 1;
		dir[1][v] += 1;
		dir[1][lca] -= 1;
		debug(u, v, lca);
		// u -> lca up 
		// v -> lca down
	}
	memset(vis, 0, sizeof(vis));
	for (int i = 1; i <= n; i++){
		if (!vis[i]){
			dfs3(i);
		}
	}
	memset(ans, -1, sizeof(ans));
	for (int i = 2; i <= n; i++){
		debug(i, dir[0][i], dir[1][i]);
		if ((!!dir[0][i])^(!!dir[1][i])){
			if (dir[1][i]){
				ans[id[i]] = (edges[id[i]].F == fa[i][0]);
			}
			if (dir[0][i]){
				ans[id[i]] = (edges[id[i]].F == i);
			}
		}
	}
	for (int i = 1; i <= m; i++){
		if (ans[i] == -1){
			cout << 'B';
		} else if (ans[i] == 1) {
			cout << 'R';
		}
		else {
			cout << 'L';
		}
	}
	cout << endl;
}

Compilation message

oneway.cpp: In function 'void dfs1(int, int)':
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:29:2: note: in expansion of macro 'debug'
   29 |  debug(node, par);
      |  ^~~~~
oneway.cpp:36:12: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   36 |  for (auto [to, idx] : adj[node]){
      |            ^
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:40:5: note: in expansion of macro 'debug'
   40 |     debug(node, to, par, "!");
      |     ^~~~~
oneway.cpp: In function 'void dfs3(int)':
oneway.cpp:56:12: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   56 |  for (auto [to, idx] : adj[node]){
      |            ^
oneway.cpp: In function 'int main()':
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:97:3: note: in expansion of macro 'debug'
   97 |   debug(i, dir[0][i], dir[1][i]);
      |   ^~~~~
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:99:2: note: in expansion of macro 'debug'
   99 |  debug("E");
      |  ^~~~~
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:110:3: note: in expansion of macro 'debug'
  110 |   debug(u, v, lca);
      |   ^~~~~
oneway.cpp:6:20: warning: statement has no effect [-Wunused-value]
    6 | #define debug(...) 42
      |                    ^~
oneway.cpp:122:3: note: in expansion of macro 'debug'
  122 |   debug(i, dir[0][i], dir[1][i]);
      |   ^~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4696 KB Output is correct
2 Correct 2 ms 4700 KB Output is correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 1 ms 4700 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 1 ms 4700 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 2 ms 4700 KB Output is correct
9 Correct 1 ms 4700 KB Output is correct
10 Correct 2 ms 4700 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4696 KB Output is correct
2 Correct 2 ms 4700 KB Output is correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 1 ms 4700 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 1 ms 4700 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 2 ms 4700 KB Output is correct
9 Correct 1 ms 4700 KB Output is correct
10 Correct 2 ms 4700 KB Output is correct
11 Correct 26 ms 13356 KB Output is correct
12 Correct 32 ms 14252 KB Output is correct
13 Correct 36 ms 17492 KB Output is correct
14 Correct 41 ms 20164 KB Output is correct
15 Correct 39 ms 20052 KB Output is correct
16 Correct 31 ms 18268 KB Output is correct
17 Correct 34 ms 19800 KB Output is correct
18 Correct 30 ms 18276 KB Output is correct
19 Correct 38 ms 21100 KB Output is correct
20 Correct 34 ms 15952 KB Output is correct
21 Correct 28 ms 15700 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4696 KB Output is correct
2 Correct 2 ms 4700 KB Output is correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 1 ms 4700 KB Output is correct
5 Correct 1 ms 4956 KB Output is correct
6 Correct 1 ms 4700 KB Output is correct
7 Correct 1 ms 4956 KB Output is correct
8 Correct 2 ms 4700 KB Output is correct
9 Correct 1 ms 4700 KB Output is correct
10 Correct 2 ms 4700 KB Output is correct
11 Correct 26 ms 13356 KB Output is correct
12 Correct 32 ms 14252 KB Output is correct
13 Correct 36 ms 17492 KB Output is correct
14 Correct 41 ms 20164 KB Output is correct
15 Correct 39 ms 20052 KB Output is correct
16 Correct 31 ms 18268 KB Output is correct
17 Correct 34 ms 19800 KB Output is correct
18 Correct 30 ms 18276 KB Output is correct
19 Correct 38 ms 21100 KB Output is correct
20 Correct 34 ms 15952 KB Output is correct
21 Correct 28 ms 15700 KB Output is correct
22 Correct 92 ms 21072 KB Output is correct
23 Correct 83 ms 19540 KB Output is correct
24 Correct 62 ms 19536 KB Output is correct
25 Correct 90 ms 23896 KB Output is correct
26 Correct 88 ms 20564 KB Output is correct
27 Correct 71 ms 19396 KB Output is correct
28 Correct 30 ms 8784 KB Output is correct
29 Correct 77 ms 16720 KB Output is correct
30 Correct 72 ms 16976 KB Output is correct
31 Correct 75 ms 17232 KB Output is correct
32 Correct 79 ms 21072 KB Output is correct