Compilare: main.cpp: In function 'void dijkstra(Graph&)': main.cpp:47:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g.adj_list[node].size(); i++) { ~~^~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:58:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2; i < dist.size(); i++) { ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:67:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.in", "r", stdin); ^ main.cpp:68:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.out", "w", stdout); ^