Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:15:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<L[nod].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:35:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<L[i].size();j++){ ^ user.cpp:36:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=j+1;k<L[i].size();k++){ ^ user.cpp:25:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&x); ^ user.cpp:30:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&a,&b,&c); ^