Compilare: main.cpp: In function 'void dijkstra(int)': main.cpp:25:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<g[k].size();j++) ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:38:41: 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:39:43: 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); ^ main.cpp:40:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ main.cpp:44:39: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&x,&y,&c); ^