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Código do problema Países em Guerra. Implementem o algoritmo de Dijkstra
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#include <climits> | |
#include <iostream> | |
#include <vector> | |
#include <queue> | |
#include <stack> | |
#include <algorithm> | |
const int infinity = INT_MAX; | |
const int BLACK = 2; | |
const int GREY = 1; | |
const int WHITE = 0; | |
using namespace std; | |
//return the sc component from node i | |
void dfs_sc(vector<vector<int>>& g,vector<vector<int>>& sc,int v, vector<int>& visited, vector<int>& index,vector<int>& low, int& dfs_n){ | |
static stack<int> s; | |
index[v] = dfs_n; | |
low[v] = dfs_n; | |
dfs_n++; | |
s.push(v); | |
visited[v] = GREY; | |
for(int u=1;u<g.size();u++){ | |
if(g[v][u]>=0){ | |
if(visited[u]==WHITE){ | |
dfs_sc(g,sc,u,visited,index,low,dfs_n); | |
low[v] = min(low[v],low[u]); | |
} | |
else if(visited[u]==GREY){ | |
low[v] = min(low[v],index[u]); | |
} | |
} | |
} | |
visited[v] = BLACK; | |
if(index[v]==low[v]){ | |
vector<int> scc; | |
int w; | |
do{ | |
w = s.top(); | |
s.pop(); | |
scc.push_back(w); | |
}while(w!=v); | |
sc.push_back(scc); | |
} | |
} | |
void strong_components(vector<vector<int>>& graph){ | |
vector<int> visited(graph.size(),0); | |
vector<int> index(graph.size()); | |
vector<int> low(graph.size()); | |
vector<vector<int>> sc; | |
stack<int> s1; | |
stack<int> s2; | |
int dfs_n = 1; | |
for(int i=1;i<graph.size();i++){ | |
if(visited[i]==WHITE){ | |
//do a DFS searching for strong components | |
dfs_sc(graph,sc,i,visited,index,low,dfs_n); | |
} | |
} | |
for(int i=0;i<sc.size();i++){ | |
for(int j=0;j<sc[i].size();j++){ | |
for(int k=0;k<sc[i].size();k++){ | |
graph[sc[i][j]][sc[i][k]] = 0; | |
graph[sc[i][k]][sc[i][j]] = 0; | |
} | |
} | |
} | |
} | |
int main(){ | |
int n,e; | |
while(cin >> n >> e && (n || e)){ | |
vector<vector<int>> graph(n+1,vector<int>(n+1,-1)); | |
for(int i=0;i<e;i++){ | |
int x,y,h; | |
cin >> x >> y >> h; | |
graph[x][y] = h; | |
} | |
strong_components(graph); | |
int k; | |
cin >> k; | |
for(int i=0;i<k;i++){ | |
int o,k; | |
cin >> o >> k; | |
//djikstra(graph,o,k); IMPLEMENTE O DIJKSTRA | |
} | |
cout << "\n"; | |
} | |
return 0; | |
} |
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