Compilare: user.cpp: In function ‘int main()’: user.cpp:36:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("perioada01.in", "r", stdin); ^ user.cpp:37:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("perioada01.out", "w", stdout); ^ user.cpp: In function ‘void next_int(int&)’: user.cpp:13:45: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, buffer_size, stdin); ^ user.cpp:18:49: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, buffer_size, stdin); ^ user.cpp:25:49: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, buffer_size, stdin); ^