Compilare: main.cpp: In function 'int main()': main.cpp:60:23: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::set<std::pair<int, int> >::size_type {aka long unsigned int}' [-Wformat=] printf("%d\n",s.size()); ^ main.cpp:25:27: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ar.in","r",stdin); ^ main.cpp:26:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ar.out","w",stdout); ^ main.cpp:28:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&r2); ^ main.cpp:31:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^