Compilare: user.cpp: In function ‘int main()’: user.cpp:80:31: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘std::set<int>::size_type {aka long unsigned int}’ [-Wformat=] printf("%d\n" , A1.size()); ^ user.cpp:86:30: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘std::set<int>::size_type {aka long unsigned int}’ [-Wformat=] printf("%d\n", A2.size()); ^ user.cpp:67:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pamant.in" , "r" ,stdin); ^ user.cpp:68:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pamant.out" , "w", stdout); ^ user.cpp: In function ‘void Read()’: user.cpp:21:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &N ,&M); ^ user.cpp:26:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^