Compilare: main.cpp: In function 'int main()': main.cpp:51:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(myset.size() == n+m-1) ~~~~~~~~~~~~~^~~~~~~~ main.cpp:31:31: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(s, 1, 22500000, fin); ^