Compilare: user.cpp: In function ‘int main()’: user.cpp:23:26: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[301]’ [-Wformat=] scanf ( "%s", &s1); ^ user.cpp:24:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i <strlen (s1); i++) ~~^~~~~~~~~~~~ user.cpp:26:25: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[301]’ [-Wformat=] scanf ("%s", &s2); ^ user.cpp:27:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i <strlen (s2); i++) ~~^~~~~~~~~~~~ user.cpp:29:25: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[301]’ [-Wformat=] scanf ("%s", &s3); ^ user.cpp:31:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i <strlen (s3); i++) ~~^~~~~~~~~~~~ user.cpp:16:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("entropy.in","r",stdin); ^ user.cpp:17:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("entropy.out","w",stdout); ^ user.cpp:23:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%s", &s1); ^ user.cpp:26:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%s", &s2); ^ user.cpp:29:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%s", &s3); ^