Compilare: user.cpp: In function ‘int main()’: user.cpp:50:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();i++) ~^~~~~~~~~~~ user.cpp:52:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<sol[i].size();j++) ~^~~~~~~~~~~~~~ user.cpp:28:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&V,&E); ^ user.cpp:33:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&x,&y); ^