Compilare: main.cpp: In function 'int main()': main.cpp:20:44: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::unordered_set<int>::size_type {aka long unsigned int}' [-Wformat=] fprintf(fout,"%d\n",st.count(x)); ^ main.cpp:10:24: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&n); ^ main.cpp:13:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d %d",&t,&x); ^