Compilare: user.cpp: In function ‘int main()’: user.cpp:36:33: 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:37:35: 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:40:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(sir+1); ^ user.cpp:43:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&n); ^ user.cpp:46:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&c); ^ user.cpp: In function ‘int solve()’: user.cpp:26:19: warning: ‘x’ may be used uninitialized in this function [-Wmaybe-uninitialized] p=p&(x^t); ^ /tmp/ccoxvYUy.o: In function `main': user.cpp:(.text.startup+0x64): warning: the `gets' function is dangerous and should not be used.