Compilare: user.cpp: In function ‘int main()’: user.cpp:12:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("palind.in","r",stdin); ^ user.cpp:13:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("palind.out","w",stdout); ^ user.cpp:15:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (scanf("%d\n", &T); T ; --T) ^ user.cpp:17:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(sir + 1); lenght = strlen(sir + 1); ^ /tmp/cc60j0g6.o: In function `main': user.cpp:(.text.startup+0x7d): warning: the `gets' function is dangerous and should not be used.