Compilare: user.cpp: In function ‘void read_tree(int)’: user.cpp:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void represent_tree(nod*, char*&)’: user.cpp:38: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void read_data()’: user.cpp:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘bool kmp(char*, char*)’: user.cpp:81: warning: unused variable ‘i’ user.cpp: In function ‘int main()’: user.cpp:140: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:141: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result