Compilare: user.cpp: In function ‘int main()’: user.cpp:95:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v[i].x.size()<k) ~~~~~~~~~~~~~^~ user.cpp:104:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v[*it].x.size()<k) ~~~~~~~~~~~~~~~^~ user.cpp:113:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v[i].x.size()>=k){ ~~~~~~~~~~~~~^~~ user.cpp:59:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d%d ",&n,&m,&k); ^