Compilare: user.cpp: In function ‘int main()’: user.cpp:134:51: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("infinitepatternmatching.in", "r", stdin); ^ user.cpp:135:53: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("infinitepatternmatching.out", "w", stdout); ^ user.cpp:138:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", A + 1); ^