Compilare: user.cpp: In function ‘void read()’: user.cpp:11:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("subsir.in", "r", stdin); ^ user.cpp:13:30: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(a + 1, Nmax, stdin); ^ user.cpp:14:30: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(b + 1, Nmax, stdin); ^ user.cpp: In function ‘void solve()’: user.cpp:54:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("subsir.out", "w", stdout); ^ In file included from /usr/include/stdio.h:934:0, from user.cpp:1: In function ‘char* fgets(char*, int, FILE*)’, inlined from ‘void read()’ at user.cpp:13:30: /usr/include/i386-linux-gnu/bits/stdio2.h:253:58: warning: call to ‘__fgets_chk_warn’ declared with attribute warning: fgets called with bigger size than length of destination buffer [enabled by default] return __fgets_chk_warn (__s, __bos (__s), __n, __stream); ^ In function ‘char* fgets(char*, int, FILE*)’, inlined from ‘void read()’ at user.cpp:14:30: /usr/include/i386-linux-gnu/bits/stdio2.h:253:58: warning: call to ‘__fgets_chk_warn’ declared with attribute warning: fgets called with bigger size than length of destination buffer [enabled by default] return __fgets_chk_warn (__s, __bos (__s), __n, __stream); ^