Compilare: main.cpp: In function 'int main()': main.cpp:68:26: 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:33:30: 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:34:32: 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:36:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &R); ^ main.cpp:40:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^