답안 #478968

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
478968 2021-10-09T09:22:46 Z hjc4vr Pipes (CEOI15_pipes) C++14
100 / 100
1431 ms 16120 KB
#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;
 
typedef long double ld;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<pl> vpl;
typedef vector<ld> vld;
typedef pair<ld, ld> pld;
typedef vector<pi> vpi;
 
//typedef tree<ll, null_type, less_equal<ll>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
template<typename T>
ostream &operator<<(ostream &os, vector<T> &a) {
    os << "[";
    for (int i = 0; i < ll(a.size()); i++) { os << a[i] << ((i != ll(a.size() - 1) ? " " : "")); }
    os << "]\n";
    return os;
}
 
#define all(x) x.begin(),x.end()
#define YES out("YES")
#define NO out("NO")
#define out(x){cout << x << "\n"; return;}
#define GLHF ios_base::sync_with_stdio(false); cin.tie(NULL);cout.tie(NULL)
#define print(x){for(auto ait:x) cout << ait << " "; cout << "\n";}
#define pb push_back
#define umap unordered_map
 
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
    is >> p.first >> p.second;
    return is;
}
 
template<typename T1, typename T2>
ostream &operator<<(ostream &os, pair<T1, T2> &p) {
    os << "" << p.first << " " << p.second << "";
    return os;
}
 
void usaco(string taskname) {
    string fin = taskname + ".in";
    string fout = taskname + ".out";
    const char *FIN = fin.c_str();
    const char *FOUT = fout.c_str();
    freopen(FIN, "r", stdin);
    freopen(FOUT, "w", stdout);
}
 
template<typename T>
void read(vector<T> &v) {
    int n = v.size();
    for (int i = 0; i < n; i++)
        cin >> v[i];
}
 
template<typename T>
vector<T> UNQ(vector<T> a) {
    vector<T> ans;
    for (T t: a)
        if (ans.empty() || t != ans.back())
            ans.push_back(t);
    return ans;
}
 
ll ceil(ll a, ll b) {
    ll ans = a / b;
    if (a % b)ans++;
    return ans;
}
 
ld log(ld a, ld b) { return log(b) / log(a); }
 
ll power(ll base, ll exp, ll M = 1e18) {//(base^exp)%M
    ll ans = 1;
    while (exp) {
        if (exp % 2 == 1)ans = ((ans % M) * (base % M)) % M;
        base = ((base % M) * (base % M)) % M;
        exp /= 2;
    }
    return ans;
}
 
string to_base(int n, int new_base) {
    string s;
    int nn = n;
    while (nn) {
        s += to_string(nn % new_base);
        nn /= new_base;
    }
    reverse(all(s));
    return s;
}
 
ll gcd(ll a, ll b) {
    if (a < b)swap(a, b);
    if (b == 0)return a;
    return gcd(b, a % b);
}
 
ll lcm(ll a, ll b) {
    ll x = (a / gcd(a, b));
    return b * x;
}
 
vl generate_array(ll n, ll mn = 1, ll mx = 1e18 + 1) {
    if (mx == 1e18 + 1)
        mx = n;
    vl ans(n);
    for (int i = 0; i < n; i++)
        ans[i] = (mn + rand() % (mx - mn + 1));
    return ans;
}
 
string substr(string s, int l, int r) {
    string ans;
    for (int i = l; i <= r; i++)
        ans += s[i];
    return ans;
}
 
 
void solve();
 
int main() {
    GLHF;
    int t = 1;
    //cin >> t;
    while (t--)
        solve();
}
 
 
 
const int maxn=1e5+1;
int par1[maxn],par2[maxn];
int get1(int x){return par1[x]=(x==par1[x]?x:get1(par1[x]));}
int get2(int x){return par2[x]=(x==par2[x]?x:get2(par2[x]));}
 
void unite1(int u,int v){
    u=get1(u);
    v=get1(v);
    if(u==v)
        return;
    par1[u]=v;
}
 
void unite2(int u,int v){
    u=get2(u);
    v=get2(v);
    if(u==v)
        return;
    par2[u]=v;
}
int t = 0;
int dis[maxn], lo[maxn];
vector< int > graph[maxn];
void dfs(int x, int parr) {
    dis[x] = t++;
    lo[x] = dis[x];
    //printf("start %d %d\n", x, dis[x]);
 
    bool flag = false;
    for (int tren : graph[x]) {
        if (tren == parr && !flag) {
            flag = true;
            continue;
        }
        if (dis[tren] == -1) {
            dfs(tren, x);
            if (lo[tren] > dis[x]) cout <<  x << " " <<  tren << "\n";
            lo[x] = min(lo[x], lo[tren]);
        } else {
            lo[x] = min(lo[x], dis[tren]);
        }
    }
    //printf("end %d: %d %d\n", x, dis[x], lo[x]);
}
 
 
void solve() {
    int n,m;
    cin >> n >> m;
 
 
    for(int i=1; i<=n; i++)
        par1[i]=par2[i]=i;
 
    for(int i=0; i<m; i++){
        int u,v;
        cin >> u >> v;
        if(get1(u)!=get1(v)){
            unite1(u,v);
            graph[u].pb(v);
            graph[v].pb(u);
        }
        else if(get2(u)!=get2(v)){
            unite2(u,v);
            graph[u].pb(v);
            graph[v].pb(u);
        }
    }
 
    memset(dis, -1, sizeof dis);
    for (int i = 1; i <= n; i++) {
        if (dis[i] == -1) dfs(i, 0);
    }
 
}

Compilation message

pipes.cpp: In function 'void usaco(std::string)':
pipes.cpp:57:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   57 |     freopen(FIN, "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~
pipes.cpp:58:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   58 |     freopen(FOUT, "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 3020 KB Output is correct
2 Correct 2 ms 3020 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 3468 KB Output is correct
2 Correct 5 ms 3276 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 135 ms 3344 KB Output is correct
2 Correct 117 ms 3204 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 220 ms 4032 KB Output is correct
2 Correct 219 ms 3524 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 316 ms 5588 KB Output is correct
2 Correct 267 ms 6988 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 441 ms 10620 KB Output is correct
2 Correct 421 ms 7304 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 732 ms 11784 KB Output is correct
2 Correct 639 ms 9180 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 967 ms 14320 KB Output is correct
2 Correct 1032 ms 9216 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1200 ms 16120 KB Output is correct
2 Correct 1156 ms 9104 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1431 ms 15464 KB Output is correct
2 Correct 1315 ms 12612 KB Output is correct