Compilare: user.cpp: In function ‘int main()’: user.cpp:14:35: warning: integer overflow in expression [-Woverflow] const unsigned sz = 2048*1024*1024; ^ user.cpp: In function ‘void main2()’: user.cpp:5:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("adunare.in", "r", stdin); ^ user.cpp:6:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("adunare.out", "w", stdout); ^ user.cpp:8:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^