Compilare: user.cpp: In function ‘int main()’: user.cpp:38:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bool.in","r",stdin); ^ user.cpp:39:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bool.out","w",stdout); ^ user.cpp:41:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ user.cpp:61:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (scanf("%d\n", &Q); Q; --Q) ^ user.cpp:64:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &c); ^ /tmp/ccPVoXOO.o: In function `main': user.cpp:(.text.startup+0x5d): warning: the `gets' function is dangerous and should not be used.