#include <iostream>
#include <bits/stdc++.h>
using namespace std;
struct hash_pair {
template <class T1, class T2>
size_t operator()(const pair<T1, T2>& p) const
{
auto hash1 = hash<T1>{}(p.first);
auto hash2 = hash<T2>{}(p.second);
return hash1 ^ hash2;
}
};
class graph
{
struct muchie
{
int from, to, cost;
muchie(int _from, int _to, int _cost):
from(_from), to(_to), cost(_cost)
{
}
};
public:
void bfs();
///////////////////////////////////////////////////////////
void dfs();
void _dfs_rec(int s, int viz[], vector<int> la[]);
///////////////////////////////////////////////////////////
void ctc();
void topo_dfs(int s, vector<int>& topo, int viz[], vector<int> la[]);
void dfs_lat(int el, int viz[], vector<int> lat[], vector<vector<int>>& cc);
///////////////////////////////////////////////////////////
void sortaret();
///////////////////////////////////////////////////////////
void mcritice();
void dfs_critice(int s, int p, int viz[], vector<int> la[], int lowLink[], int ids[], int& id, vector<pair<int,int>>& critice);
///////////////////////////////////////////////////////////
void biconex();
void dfs_biconexe(int s, int viz[], vector<int> la[], unordered_map<pair<int,int>, int, hash_pair>& map_critice, vector<vector<int>>& biconexe);
///////////////////////////////////////////////////////////
void havel();
///////////////////////////////////////////////////////////
void apm();
pair<int,int> get_parent_and_depth(int x, int parent[]);
///////////////////////////////////////////////////////////
void disjoint();
///////////////////////////////////////////////////////////
void dijkstra();
///////////////////////////////////////////////////////////
void bellmanford();
};
void graph::bfs()
{
ifstream f("bfs.in");
ofstream g("bfs.out");
int n,m,s;
vector<int>* la = new vector<int>[100005];
int* dist = new int[100005];
f >> n >> m >> s;
memset(dist, -1, sizeof(int) * (n+1));
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
}
int curr_dist = 1;
queue<int> q;
q.push(s);
dist[s] = 0;
while (q.size())
{
for (auto& v: la[q.front()])
{
if (dist[v] == -1)
{
dist[v] = dist[q.front()] + 1;
q.push(v);
}
}
q.pop();
}
for (int i = 1; i <= n; i++)
g << dist[i] << ' ';
delete[] dist;
delete[] la;
}
void graph::_dfs_rec(int s, int viz[], vector<int> la[])
{
viz[s] = 1;
for (auto& el: la[s])
{
if (viz[el] == 0)
_dfs_rec(el, viz, la);
}
}
void graph::dfs()
{
ifstream f("dfs.in");
ofstream g("dfs.out");
int n,m;
vector<int>* la = new vector<int>[100005];
int* viz = new int[100005];
f >> n >> m;
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
la[y].push_back(x);
}
int cc = 0;
for (int i = 1; i <= n; i++)
{
if (viz[i] == 0)
{
_dfs_rec(i, viz, la);
cc++;
}
}
g << cc;
delete[] viz;
delete[] la;
}
void graph::topo_dfs(int s, vector<int>& topo, int viz[], vector<int> la[])
{
viz[s] = 1;
for (auto& el: la[s])
{
if (viz[el] == 0)
topo_dfs(el, topo, viz, la);
}
topo.push_back(s);
}
void graph::dfs_lat(int s, int viz[], vector<int> lat[], vector<vector<int>>& cc)
{
viz[s] = 1;
cc[cc.size() - 1].push_back(s);
for (auto& el: lat[s])
{
if (viz[el] == 0)
dfs_lat(el, viz, lat, cc);
}
}
void graph::ctc()
{
ifstream f("ctc.in");
ofstream g("ctc.out");
int n,m;
vector<int>* la = new vector<int>[100005];
vector<int>* lat = new vector<int>[100005];
int* viz = new int[100005];
f >> n >> m;
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
lat[y].push_back(x);
}
vector<int> topo;
for (int i = 1; i <= n; i++)
{
if (viz[i] == 0)
{
topo_dfs(i, topo, viz, la);
}
}
// reverse topo
reverse(topo.begin(), topo.end());
// reset viz
memset(viz, 0, sizeof(int) * (n+1));
vector<vector<int>> cc;
for (auto el: topo)
{
if (!viz[el])
{
cc.push_back(vector<int>());
dfs_lat(el, viz, lat, cc);
}
}
g << cc.size() << '\n';
for (auto& row: cc)
{
for (auto& el: row)
g << el << ' ';
g << '\n';
}
delete[] la;
delete[] lat;
delete[] viz;
}
void graph::sortaret()
{
ifstream f("sortaret.in");
ofstream g("sortaret.out");
int n,m;
vector<int>* la = new vector<int>[100005];
int* viz = new int[100005];
f >> n >> m;
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
}
vector<int> topo;
for (int i = 1; i <= n; i++)
{
if (viz[i] == 0)
{
topo_dfs(i, topo, viz, la);
}
}
// reverse topo
reverse(topo.begin(), topo.end());
for (auto& el: topo)
g << el << ' ';
delete[] la;
delete[] viz;
}
void graph::dfs_critice(int s, int p, int viz[],vector<int> la[], int lowLink[], int ids[], int& id, vector<pair<int,int>>& critice)
{
lowLink[s] = id;
ids[s] = id;
id ++;
viz[s] = 1;
for (auto& el: la[s])
{
if (!viz[el])
dfs_critice(el, s, viz, la, lowLink, ids, id, critice);
if (el != p)
lowLink[s] = min(lowLink[s], lowLink[el]);
}
if (lowLink[s] == ids[s] && p != -1)
{
critice.push_back({s, p});
}
}
void graph::mcritice()
{
ifstream f("mcritice.in");
ofstream g("mcritice.out");
int n,m;
vector<int>* la = new vector<int>[100005];
int* viz = new int[100005];
int* lowLink = new int[100005];
int* ids = new int[100005];
int id = 0;
f >> n >> m;
memset(lowLink, -1, sizeof(int) *(n+1));
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
la[y].push_back(x);
}
vector<pair<int,int>> critice;
// in problema e graf conex, but anyway
for (int i = 1; i <= n; i++)
{
if (!viz[i])
dfs_critice(i, -1, viz, la, lowLink, ids, id, critice);
}
for (auto& per: critice)
g << per.first << ' ' << per.second << '\n';
delete[] viz;
delete[] la;
delete[] lowLink;
delete[] ids;
}
void graph::dfs_biconexe(int s, int viz[], vector<int> la[], unordered_map<pair<int,int>, int, hash_pair>& map_critice, vector<vector<int>>& biconexe)
{
viz[s] = 1;
biconexe[biconexe.size() - 1].push_back(s);
for (auto& el: la[s])
{
// daca e in map_critice nu e bn
if (map_critice.find({s, el}) != map_critice.end() || map_critice.find({el ,s}) != map_critice.end())
continue;
if (!viz[el])
dfs_biconexe(el, viz, la, map_critice, biconexe);
}
}
void graph::biconex()
{
// mai intai caut muchile critice
// fiecare muchie critica va fi o componente biconexa
// elimin muhcile din lista de adiacenta si fac restul de componente conexe, care vor fi si ele biconexe (in afara de cele cu un singur nod)
ifstream f("biconex.in");
ofstream g("biconex.out");
int n,m;
vector<int>* la = new vector<int>[100005];
int* viz = new int[100005];
int* lowLink = new int[100005];
int* ids = new int[100005];
int id = 0;
f >> n >> m;
memset(lowLink, -1, sizeof(int) *(n+1));
for (int i = 1; i <= m; i++)
{
int x,y;
f >> x >> y;
la[x].push_back(y);
la[y].push_back(x);
}
vector<pair<int,int>> critice;
// in problema e graf conex, but anyway
for (int i = 1; i <= n; i++)
{
if (!viz[i])
dfs_critice(i, -1, viz, la, lowLink, ids, id, critice);
}
// inserez in biconexe toate muchile critice
vector<vector<int>> biconexe;
for (auto& per: critice)
{
biconexe.push_back(vector<int>());
biconexe[biconexe.size()-1].push_back(per.first);
biconexe[biconexe.size()-1].push_back(per.second);
}
// pastrez aici muchile care sunt critice pt a nu le folosi in dfs final
unordered_map<pair<int,int>, int, hash_pair> map_critice;
for (auto& per: critice)
{
map_critice[{per.first, per.second}] = 1;
map_critice[{per.second, per.first}] = 1;
}
int nrBic = critice.size();
memset(viz, 0, sizeof(int) * (n+1));
for (int i = 1; i <= n; i++)
{
if (!viz[i])
{
biconexe.push_back(vector<int>());
dfs_biconexe(i, viz, la, map_critice, biconexe);
if (biconexe[biconexe.size()-1].size() >= 2)
nrBic ++;
}
}
g << nrBic << '\n';
for (auto& row: biconexe)
{
if (row.size() < 2)
continue;
for (auto& el: row)
g << el << ' ';
g << '\n';
}
delete[] viz;
delete[] la;
delete[] lowLink;
delete[] ids;
}
void graph::havel()
{
ifstream f("havel.in");
ofstream g("havel.out");
int n;
f >> n;
vector<int> v;
for (int i = 0; i < n; i++)
{
int x;
f >> x;
v.push_back(x);
}
sort(v.begin(), v.end(), [](int x, int y){return x > y;});
for (int i = 0; i < n; i++)
{
for (int j = i+1; j < n; j++)
{
if (v[i] == 0)
break;
if (v[j])
{
v[j] --;
v[i] --;
}
}
if (v[i] > 0)
{
cout << "NU";
return;
}
}
cout << "DA";
}
pair<int,int> graph::get_parent_and_depth(int x, int parent[])
{
vector<int> met_on_the_way;
int h = 0;
while (parent[x] != 0 && parent[x] != -1)
{
met_on_the_way.push_back(x);
h ++;
x = parent[x];
}
for (auto el: met_on_the_way)
parent[el] = x;
return {x, h};
}
void graph::apm()
{
ifstream f("apm.in");
ofstream g("apm.out");
int n,m;
vector<muchie> edges;
int* parent = new int[100005];
int id = 0;
f >> n >> m;
memset(parent, -1, sizeof(int) *(n+1));
for (int i = 1; i <= m; i++)
{
int x,y,c;
f >> x >> y >> c;
edges.push_back({x,y,c});
}
sort(edges.begin(), edges.end(), [](muchie& m1, muchie& m2) {return (m1.cost < m2.cost);});
vector<pair<int,int>> sol;
int s = 0;
for (auto& m: edges)
{
// first va contine parintele iar second va contine inaltimea
pair<int,int> info_from = get_parent_and_depth(m.from, parent);
pair<int,int> info_to = get_parent_and_depth(m.to, parent);
// daca au parinte diferit, le unim si adaugam la solutie
if (info_from.first != info_to.first)
{
s += m.cost;
sol.push_back({m.from, m.to});
// from e mai inalt il facem pe second copil
if (info_from.second > info_to.second)
parent[info_to.first] = info_from.first;
else
parent[info_from.first] = info_to.first;
}
}
g << s << '\n';
g << sol.size() << '\n';
for (auto& per: sol)
g << per.first << ' ' << per.second << '\n';
delete[] parent;
}
void graph::disjoint()
{
ifstream f("disjoint.in");
ofstream g("disjoint.out");
int n, nrop;
int* parent = new int[100005];
int id = 0;
f >> n >> nrop;
memset(parent, -1, sizeof(int) *(n+1));
for (int i = 1; i <= nrop; i++)
{
int tip, from, to;
f >> tip >> from >> to;
pair<int,int> info_from = get_parent_and_depth(from, parent);
pair<int,int> info_to = get_parent_and_depth(to, parent);
if (tip == 1)
{
if (info_from.second > info_to.second)
{
parent[info_to.first] = info_from.first;
}
else
{
parent[info_from.first] = info_to.first;
}
}
else
{
if (info_from.first == info_to.first)
g << "DA\n";
else
g << "NU\n";
}
}
delete[] parent;
}
void graph::dijkstra()
{
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n,m;
f >> n >> m;
vector<pair<int,int>>* la = new vector<pair<int,int>>[n+1];
int* dist = new int[n+1];
for (int i = 1; i <= n; i++)
dist[i] = 999999999;
for (int i = 1; i <= m; i++)
{
int x,y,c;
f >> x >> y >> c;
la[x].push_back({y,c});
}
dist[1] = 0;
priority_queue<pair<int,int>> pq;
pq.push({0, 1});
while (pq.size())
{
pair<int,int> top = pq.top(); // top second este nodul ale carui muchii le vom parcurge acum, top first este costul de a ajunge la el
pq.pop();
for (auto el: la[top.second])
{
if (dist[el.first] > dist[top.second] + el.second)
{
dist[el.first] = dist[top.second] + el.second;
pq.push({-el.second, el.first});
}
}
}
for (int i = 2; i <= n; i++)
{
if (999999999 == dist[i])
dist[i] = 0;
g << dist[i] << ' ';
}
delete[] la;
delete[] dist;
}
void graph::bellmanford()
{
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
int n,m;
f >> n >> m;
int* dist = new int[n+1];
int* used = new int[n+1];
vector<pair<int,int>>* la = new vector<pair<int,int>>[n+1];
for (int i = 1; i <= n; i++)
dist[i] = 999999999;
for (int i = 1; i <= m; i++)
{
int x,y,c;
f >> x >> y >> c;
la[x].push_back({y,c});
}
vector<int> to_check_now;
to_check_now.push_back(1);
dist[1] = 0;
for (int k = 1; k <= n && to_check_now.size(); k++)
{
vector<int> to_check_next;
for (int i = 1; i <= n; i++)
used[i] = 0;
for (auto el: to_check_now)
{
for (auto& m: la[el])
{
if (dist[m.first] > dist[el] + m.second)
{
dist[m.first] = dist[el] + m.second;
if (!used[m.first])
{
used[m.first] = 1;
to_check_next.push_back(m.first);
}
}
}
}
to_check_next.swap(to_check_now);
}
for (auto el: to_check_now)
for (auto& m: la[el])
if (dist[m.first] > dist[el] + m.second)
{
g << "Ciclu negativ!";
return;
}
for (int i = 2; i <= n; i++)
{
if (999999999 == dist[i])
dist[i] = 0;
g << dist[i] << ' ';
}
delete[] dist;
delete[] la;
delete[] used;
}
int main()
{
graph g;
g.bellmanford();
return 0;
}