Compilare: user.cpp: In function ‘void compute_prefix()’: user.cpp:25:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1; i<strlen(pattern); i++) ^ user.cpp: In function ‘void read()’: user.cpp:77:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s\n%s", pattern, s); ^