Compilare: main.cpp: In function 'int main()': main.cpp:43:35: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=] fprintf(fout,"%d\n",ans.size()); ^ main.cpp:15:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%s\n",a); ^ main.cpp:16:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%s\n",b); ^