Submission #1005155

#	Time	Username	Problem	Language	Result	Execution time	Memory
1005155		Rifal	One-Way Streets (CEOI17_oneway)	C++14	0 / 100	1 ms	7512 KiB

oneway

#include <bits/stdc++.h>
#include <fstream>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define mod 1000000007
#define INF 1000000000
#define INF2 2000000000
#define fi first
#define se second
using namespace std;
double const EPS = 1e-14;
const int P = 1007;
typedef long long ll;
using namespace __gnu_pbds;
typedef long long ll;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set; // find_by_order, order_of_key
const int Max = 1e5 + 5;
int n, m;
vector<int> v[Max]; 
set<int> st[Max];
map<pair<int,int>,int> mp, cnt;
vector<int> now;
bool vis[Max];
int nod;
void dfs(int s) {
    vis[s] = 1;
 //   cout << s << endl;
    if(st[nod].find(s) != st[nod].end()) {
        for(int i = now.size()-1; i >= 1; i--) {
          //  cout << now[i-1] << ' ' << now[i] << 'r' << endl;
            if(mp[{now[i],now[i-1]}] == 0) {
                mp[{now[i],now[i-1]}] = 3;
            }
            if(mp[{now[i-1],now[i]}] == 0) {
                mp[{now[i-1],now[i]}] = 2;
            }
        }
    }
    for(auto i : v[s]) {
        if(vis[i] == 0) {
            cnt[{s,i}]--;
            cnt[{i,s}]--;
            now.push_back(i);
            dfs(i);
            now.pop_back();
        }
        else if(cnt[{s,i}] > 0) {
            
            cnt[{s,i}]--;
            cnt[{i,s}]--;
            int last = i;
            for(int j = now.size()-1; j >= 0; j--) {
                mp[{now[j],last}] = 1;
                mp[{last,now[j]}] = 1;
                last = now[j];
                if(now[j] == i) {
                    break;
                }
            }
        }
    }

}
int main()
{
    ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
    cin >> n >> m;
    pair<int,int> edge[m];
    for(int i = 0; i < m; i++) {
        int a, b; cin >> a >> b;
        edge[i].fi = a; edge[i].se = b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    int p; cin >> p;
    vector<int> vv;
    while(p--) {
        int a, b; cin >> a >> b;
        st[a].insert(b);
        vv.push_back(a);
    }
    for(int i = 0; i < vv.size(); i++) {
        for(int j = 1; j <= n; j++) { vis[j] = 0;}
        for(int j = 0; j < m; j++) {
            cnt[{edge[j].fi,edge[j].se}]++;
            cnt[{edge[j].se,edge[j].fi}]++;
        }
        nod = vv[i];
        now.push_back(nod);
        dfs(vv[i]);
        now.pop_back();
    }
    for(int i = 0; i < m; i++) {
        int ans = mp[{edge[i].fi,edge[i].se}];
       // cout << ans << endl;
       // cout << edge[i].fi << ' ' << edge[i].se << 'l' << endl;
        if(ans <= 1) {
            cout << 'B';
        }
        else if(ans == 2) {
            cout << 'R';
        }
        else {
            cout << 'L';
        }
    }
    cout << endl;
    return 0;
}

Compilation message (stderr)

oneway.cpp: In function 'int main()':
oneway.cpp:83:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |     for(int i = 0; i < vv.size(); i++) {
      |                    ~~^~~~~~~~~~~

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