oj.uz

Submission #990620

# Submission time Handle Problem Language Result Execution time Memory
990620 2024-05-30T17:41:45 Z grogu One-Way Streets (CEOI17_oneway) C++14
100 / 100
 529 ms 93756 KB 
    // __builtin_popcount(x)
    // __builtin_popcountll(x)
    #define here cerr<<"===========================================\n"
    #include <bits/stdc++.h>
    #define ld double
    #define ll long long
    #define ull unsigned long long
    #define llinf 100000000000000000LL // 10^17
    #define iinf 2000000000 // 2*10^9
    #define pb push_back
    #define popb pop_back
    #define fi first
    #define sc second
    #define endl '\n'
    #define pii pair<int,int>
    #define pll pair<ll,ll>
    #define pld pair<ld,ld>
    #define sz(a) int(a.size())
    #define all(a) a.begin(),a.end()
    #define ceri(a,l,r) {for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
    using namespace std;
     
    #define maxn 100005
    ll n,m;
    map<pll,ll> cnt;
    map<pll,bool> ans;
    ll con[maxn];
    vector<ll> g[maxn];
    ll in[maxn];
    vector<pll> edge;
    ll it = 1;
    ll low[maxn];
    bool vis[maxn];
    stack<ll> stk;
    map<pll,bool> bio;
    map<pll,bool> most;
    ll dsu[maxn];
    ll comp = 1;
    ll csz = 0;
    void dfs(ll u,ll par){
        low[u] = in[u] = it++;
        vis[u] = 1;
        stk.push(u);
        bool moze =1;
        if(cnt[{u,par}]>1) moze = 0;
        for(ll s : g[u]){
            if(s==par){
                if(cnt[{u,par}]==1) continue;
                continue;
            }
            if(!vis[s]) dfs(s,u),low[u] = min(low[u],low[s]);
          	else low[u] = min(low[u],in[s]);
        }
        if(u==par) return;
        if(moze&&low[u]>in[par]){
            ++csz;
            while(stk.size()){
                ll to = stk.top();
                stk.pop();
                dsu[to] = csz;
                if(to==u) break;
            }
        }
    }
    ll root(ll x){
        while(x!=con[x]){
            con[x] = con[con[x]];
            x = con[x];
        }
        return x;
    }
    void upd(ll x,ll y){
        x = root(x);
        y = root(y);
        con[x] = con[y];
    }
    ll q;
    #define lg 25
    ll in2[maxn];
    ll out2[maxn];
    vector<ll> v[maxn];
    ll st[maxn][lg];
    void dfs2(ll u,ll par){
        vis[u] =1;
        st[u][0] = par;
        in2[u] = it++;
        for(ll s : v[u]){
            if(s==par) continue;
            dfs2(s,u);
        }
        out2[u] = it-1;
    }
    bool intree(ll x,ll y){
        return in2[x]>=in2[y]&&out2[y]>=out2[x];
    }
    ll lca(ll x,ll y){
        if(intree(x,y)) return y;
        if(intree(y,x)) return x;
        for(ll j = lg-1;j>=0;j--){
            if(!intree(x,st[y][j])) y = st[y][j];
        }
        return st[y][0];
    }
    map<pll,ll> mp;
    ll poc[maxn];
    ll kr[maxn];
    void dfs3(ll u,ll par){
        vis[u] = 1;
        for(ll s : v[u]){
            if(s==par) continue;
            dfs3(s,u);
            poc[u]+=poc[s];
            kr[u]+=kr[s];
        }
        mp[{u,par}] = poc[u]-kr[u];
        mp[{par,u}] = poc[u]-kr[u];
    }
    map<pll,pll> tru;
    int main(){
        ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
        cin >> n >> m;
        for(ll i = 1;i<=m;i++){
            ll x,y; cin >> x >> y;
            cnt[{x,y}]++;
            cnt[{y,x}]++;
            edge.pb({x,y});
            g[x].pb(y);
            g[y].pb(x);
        }
        fill(vis,vis+n+1,0);
        for(ll i = 1;i<=n;i++) if(vis[i]==0) dfs(i,i);
        fill(vis,vis+n+1,0);
        iota(con+1,con+n+1,1);
        //here;
        //cerr<<"DSU: "<<endl;
        //ceri(dsu,1,n);
        for(pll p : edge){
            ll x = p.fi;
            ll y = p.sc;
            if(root(dsu[x])==root(dsu[y])) continue;
            tru[{x,y}] = {dsu[x],dsu[y]};
            tru[{y,x}] = {dsu[y],dsu[x]};
            v[dsu[x]].pb(dsu[y]);
            v[dsu[y]].pb(dsu[x]);
            upd(dsu[x],dsu[y]);
        }
        it = 1;
        fill(vis,vis+n+1,0);
        for(ll i = 1;i<=n;i++) if(vis[i]==0) dfs2(i,i);
        for(ll j = 1;j<lg;j++) for(ll i = 1;i<=n;i++) st[i][j] = st[st[i][j-1]][j-1];
        cin >> q;
        bool moe = 1;
        vector<pll> upit;
        for(ll i = 1;i<=q;i++){
            ll x,y; cin >> x >> y;
            upit.pb({x,y});
            x = dsu[x];
            y = dsu[y];
            if(x==y) continue;
            if(st[x][lg-1]!=st[y][lg-1]) moe = 0;
            poc[x]++;
            kr[y]++;
            ll z = lca(x,y);
            poc[z]--;
            kr[z]--;
            //cerr<<"lca: "<<x<< " "<<y<< " "<<z<<endl;
        }
        //here;
        //cerr<<"DSU: "<<endl;
        //ceri(dsu,1,n);
        fill(vis,vis+n+1,0);
        //for(ll i = 1;i<=n;i++) cerr<<poc[i]-kr[i]<<" ";
        //cerr<<endl;
        for(ll i = 1;i<=n;i++) if(vis[i]==0) dfs3(i,i);
        //for(ll i = 1;i<=n;i++) cerr<<poc[i]-kr[i]<<" ";
        //cerr<<endl;
        //here;
        for(ll ii = 0;ii<m;ii++){
            pll p = edge[ii];
            if(p.fi==p.sc){
                cout<<'B';
                continue;
            }
            if(cnt[p]>1) cout<<'B';
            else{
                if(dsu[p.fi]==dsu[p.sc]){
                    cout<<'B';
                    //cerr<<ii<<" "<<dsu[p.fi]<<endl;
                    continue;
                }
                ll x = mp[tru[p]];
                if(x==0) cout<<'B';
                else if(x>0){
                    if(in2[dsu[p.fi]]>in2[dsu[p.sc]]) cout<<'R';
                    else cout<<'L';
                }else{
                    if(in2[dsu[p.fi]]>in2[dsu[p.sc]]) cout<<'L';
                    else cout<<'R';
                }
            }
        }
        cout<<endl;
        return 0;
    }

Compilation message

oneway.cpp: In function 'int main()':
oneway.cpp:152:14: warning: variable 'moe' set but not used [-Wunused-but-set-variable]
  152 |         bool moe = 1;
      |              ^~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11612 KB Output is correct
2 Correct 2 ms 11612 KB Output is correct
3 Correct 3 ms 11936 KB Output is correct
4 Correct 4 ms 12124 KB Output is correct
5 Correct 4 ms 12124 KB Output is correct
6 Correct 2 ms 11868 KB Output is correct
7 Correct 4 ms 12196 KB Output is correct
8 Correct 4 ms 12124 KB Output is correct
9 Correct 3 ms 11864 KB Output is correct
10 Correct 3 ms 11868 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11612 KB Output is correct
2 Correct 2 ms 11612 KB Output is correct
3 Correct 3 ms 11936 KB Output is correct
4 Correct 4 ms 12124 KB Output is correct
5 Correct 4 ms 12124 KB Output is correct
6 Correct 2 ms 11868 KB Output is correct
7 Correct 4 ms 12196 KB Output is correct
8 Correct 4 ms 12124 KB Output is correct
9 Correct 3 ms 11864 KB Output is correct
10 Correct 3 ms 11868 KB Output is correct
11 Correct 150 ms 37436 KB Output is correct
12 Correct 168 ms 41664 KB Output is correct
13 Correct 216 ms 49432 KB Output is correct
14 Correct 261 ms 62400 KB Output is correct
15 Correct 299 ms 67516 KB Output is correct
16 Correct 503 ms 82304 KB Output is correct
17 Correct 378 ms 84560 KB Output is correct
18 Correct 503 ms 82016 KB Output is correct
19 Correct 388 ms 87484 KB Output is correct
20 Correct 189 ms 46016 KB Output is correct
21 Correct 149 ms 44988 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 11612 KB Output is correct
2 Correct 2 ms 11612 KB Output is correct
3 Correct 3 ms 11936 KB Output is correct
4 Correct 4 ms 12124 KB Output is correct
5 Correct 4 ms 12124 KB Output is correct
6 Correct 2 ms 11868 KB Output is correct
7 Correct 4 ms 12196 KB Output is correct
8 Correct 4 ms 12124 KB Output is correct
9 Correct 3 ms 11864 KB Output is correct
10 Correct 3 ms 11868 KB Output is correct
11 Correct 150 ms 37436 KB Output is correct
12 Correct 168 ms 41664 KB Output is correct
13 Correct 216 ms 49432 KB Output is correct
14 Correct 261 ms 62400 KB Output is correct
15 Correct 299 ms 67516 KB Output is correct
16 Correct 503 ms 82304 KB Output is correct
17 Correct 378 ms 84560 KB Output is correct
18 Correct 503 ms 82016 KB Output is correct
19 Correct 388 ms 87484 KB Output is correct
20 Correct 189 ms 46016 KB Output is correct
21 Correct 149 ms 44988 KB Output is correct
22 Correct 414 ms 87352 KB Output is correct
23 Correct 464 ms 84596 KB Output is correct
24 Correct 529 ms 84796 KB Output is correct
25 Correct 406 ms 93756 KB Output is correct
26 Correct 435 ms 87152 KB Output is correct
27 Correct 434 ms 84768 KB Output is correct
28 Correct 58 ms 20160 KB Output is correct
29 Correct 190 ms 47728 KB Output is correct
30 Correct 174 ms 47808 KB Output is correct
31 Correct 189 ms 48768 KB Output is correct
32 Correct 220 ms 59192 KB Output is correct