Compilare: user.cpp: In function ‘long long int first_val(long long int, long long int)’: user.cpp:76:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:112:51: 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:113:53: 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:117:37: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (sir + 1), L = strlen (sir + 1); ^ /tmp/cc530OlD.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.