Compilare: main.cpp: In function 'void dfs(int)': main.cpp:14:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<l[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:27:30: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&n,&m); ^ main.cpp:29:41: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&cost[i].first); ^ main.cpp:35:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&a,&b); ^