Compilare: user.cpp: In function ‘void read()’: user.cpp:20:20: warning: NULL used in arithmetic [-Wpointer-arith] while( s[i] != NULL ) ^ user.cpp:19:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp: In function ‘int main()’: user.cpp:43:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secventa.in", "r", stdin); ^ user.cpp:44:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secventa.out", "w", stdout); ^ user.cpp:45:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d\n",&n,&k); ^ /tmp/ccamNlpB.o: In function `read()': user.cpp:(.text+0x1b): warning: the `gets' function is dangerous and should not be used.