#include "bits/stdc++.h"
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
#define int long long
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define ordered_mset tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
const int INF = 1e18;
void solve(){
int n,m;
cin >> n >> m;
vector<vector<tuple<int,int,int>>> g(n + 1);
for(int i = 0;i < m;i++){
int a,b;
cin >> a >> b;
g[a].pb({b,1,i});
g[b].pb({a,0,i});
}
string f = "";
for(int i = 0;i < m;i++){
f += 'B';
}
int p;
cin >> p;
string ans = f;
int R[m + 1] {},L[m + 1] {};
for(int i = 0;i < p;i++){
int p1,p2;
cin >> p1 >> p2;
queue<int> q;
q.push(p1);
vector<tuple<int,int,int>> from(m + 1);
vector<int> dis(n + 1,INF);
dis[p1] = 0;
from[p1] = {-1,-1,-1};
while(!q.empty()){
int top = q.front();
q.pop();
for(auto [to,type,ind] : g[top]){
if(dis[top] + 1 < dis[to]){
dis[to] = dis[top] + 1;
from[to] = {top,type,ind};
q.push(to);
}
}
}
string s = f;
int now = p2;
while(now != p1){
auto[to,type,ind] = from[now];
if(type == 0){
s[ind] = 'L';
} else{
s[ind] = 'R';
}
now = to;
}
for(int j = 0;j < s.size();j++){
if(s[j] == 'R'){
R[j] = 1;
} else if(s[j] == 'L'){
L[j] = 1;
}
}
}
string res = "";
for(int i = 0;i < m;i++){
if(R[i] ^ L[i]){
if(R[i]){
res += 'R';
} else{
res += 'L';
}
} else{
res += 'B';
}
}
cout << res << "\n";
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0),cout.tie(0);
int t = 1;
// cin >> t;
while(t--){
solve();
}
}
Compilation message
oneway.cpp: In function 'void solve()':
oneway.cpp:71:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
71 | for(int j = 0;j < s.size();j++){
| ~~^~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
