Compilare: user.cpp: In function ‘void dfs_visit(unsigned int)’: user.cpp:59:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if(!(parent[u] == v) && dist[v] < dist[u]) { ^ user.cpp: In function ‘int main()’: user.cpp:80:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < no_edges; ++i) { ^ user.cpp:87:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int u = 0; u < no_nodes; ++u) { ^