Submission #478970

#	Time	Username	Problem	Language	Result	Execution time	Memory
478970		hjc4vr	Pipes (CEOI15_pipes)	C++14	Compilation error	0 ms	0 KiB

pipes

using namespace std;
int ufds1[100005],ufds2[100005],low[100005],depths[100005];
vector<int> adj[100005];
int find(int a,int par[]){
    if (par[a]==a) return a;
    par[a] = find(par[a],par);
    return par[a];
}

void dfs(int cur,int par){
    depths[cur] = depths[par] + 1;
    low[cur] = depths[cur];
    bool check= false;
    for (auto it: adj[cur]){
        if (check == false && it==par){
            check = true;
            continue;
        }
        else{
        if (depths[it]==-1){
            dfs(it,cur);
            low[cur] = min(low[cur],low[it]);
            if (low[it]>depths[cur]){
                cout << cur << ' ' << it << '\n';
            }
        }else{
            low[cur] = min(low[cur],depths[it]);
            }
        }
    }
}


int32_t main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int n,m;cin>>n>>m;
    fill(depths,depths+100005,-1);
    for (int i=1;i<=n;++i){
        ufds1[i] = i;
        ufds2[i] = i;
    }
    for (int i=0;i<m;++i){
        int a,b;cin>>a>>b;
        int pa = find(a,ufds1), pb = find(b,ufds1);
        if (pa!=pb){
            adj[a].push_back(b);
            adj[b].push_back(a);
            ufds1[pb] = pa;
        }else{ // it is a back edge
            int ba = find(a,ufds2), bb = find(b,ufds2);
            if (ba!=bb){
                adj[a].push_back(b);
                adj[b].push_back(a);
                ufds2[bb] = ba;
            }
        }
    }
    for (int i=1;i<=n;++i){
        if (depths[i]==-1){
            dfs(i,0);
        }
    }
}
   
//
//4
//4
//2
//2
//2
//4
//4
//4
//4
//2
//4
//4
//2

Compilation message (stderr)

pipes.cpp:3:1: error: 'vector' does not name a type
    3 | vector<int> adj[100005];
      | ^~~~~~
pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:14:19: error: 'adj' was not declared in this scope
   14 |     for (auto it: adj[cur]){
      |                   ^~~
pipes.cpp:22:24: error: 'min' was not declared in this scope
   22 |             low[cur] = min(low[cur],low[it]);
      |                        ^~~
pipes.cpp:24:17: error: 'cout' was not declared in this scope
   24 |                 cout << cur << ' ' << it << '\n';
      |                 ^~~~
pipes.cpp:1:1: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
  +++ |+#include <iostream>
    1 | using namespace std;
pipes.cpp:27:24: error: 'min' was not declared in this scope
   27 |             low[cur] = min(low[cur],depths[it]);
      |                        ^~~
pipes.cpp: At global scope:
pipes.cpp:34:1: error: 'int32_t' does not name a type
   34 | int32_t main(){
      | ^~~~~~~