Submission #938420

#	Time	Username	Problem	Language	Result	Execution time	Memory
938420		vjudge1	One-Way Streets (CEOI17_oneway)	C++17	30 / 100	1773 ms	17312 KiB

oneway

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pii pair<int,int>
using namespace __gnu_pbds;
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define int long long
#define s second
#define pii pair<int,int>
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
	tree_order_statistics_node_update> ordered_set;
const int N = 3e5 + 5	;
const int inf = 1e17 + 7;
const int mod = 998244353;

/*int n,m,k,a,b;
vector<int>g[N];
vector<pii>all;
vector<array<int,2>>vs(N);

void dfs(int x, vector<int>vis, map<pii,int>mp){
	
	if(x == b){
		int i = 0;
		for(auto to:all){
			if(mp[{to.f,to.s}]){
				vs[i][1] = 1;
			}
			if(mp[{to.s,to.f}]){
				vs[i][0] = 1;
			}
			i += 1;
		}
	}
	
	for(auto to:g[x]){
		if(vis[to] > vis[x] + 1){
			vis[to] = vis[x] + 1;
			mp[{x,to}] = 1;
			dfs(to,vis,mp);
		}
	}
}*/

vector<pii>g[N];
vector<int>vis(1005);
vector<pii>v,vs;

void dfs(int x, int ind){
	
	vis[x] = 1;
	
	for(auto to:g[x]){
		if(to.s == ind||vis[to.f])continue;
		dfs(to.f,ind);
	}
}

bool check(int a, int b, int ind){
	for(int i = 0;i<=1000;i++)vis[i] = 0;
	
	dfs(a,ind);
	
	if(vis[b] == 1)return true;
	else return false;
	
}

void solve(){
	
	int n,m,k;
	cin>>n>>m;
	
	for(int i = 0;i<m;i++){											
		int a,b;
		cin>>a>>b;
		g[a].pb({b,i});
		g[b].pb({a,i});
		v.pb({a,b});
	}
	
	int p;
	cin>>p;
	
	for(int i = 1;i<=p;i++){
		int a,b;
		cin>>a>>b;
		vs.pb({a,b});
	}
	
	vector<array<int,2>>ans(m + 1);
	
	for(int i = 0;i<m;i++){
		ans[i][0] = 1;
		ans[i][1] = 1;
		int x = v[i].f;
		int y = v[i].s;
		for(int j = 0;j<p;j++){
			
			int a = vs[j].f;
			int b = vs[j].s;
			if(check(a,b,i))continue;

			//Заебал го
			
			if(!check(a,x,i))ans[i][0] = 0;
			if(!check(b,y,i))ans[i][0] = 0;
			
			if(!check(a,y,i))ans[i][1] = 0;
			if(!check(b,x,i))ans[i][1] = 0;
			
		}
	}
	
	for(int i = 0;i<m;i++){
		if(ans[i][0] + ans[i][1] == 2)cout<<"B";
		else if(ans[i][0])cout<<"R";
		else cout<<"L";
	}
	
	
	
	
	
	
}

signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int tt=1;//cin>>tt>>n;
	while(tt--)solve();

}

Compilation message (stderr)

oneway.cpp: In function 'void solve()':
oneway.cpp:77:10: warning: unused variable 'k' [-Wunused-variable]
   77 |  int n,m,k;
      |          ^

• Subtask 1: 30 / 30
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40