Compilare: main.cpp: In function 'int main()': main.cpp:42:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<v.size();++i) ~^~~~~~~~~ main.cpp:26:24: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&n); ^ main.cpp:29:42: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d %d",&left, &right); ^