Compilare: user.cpp: In function ‘void back(int, int)’: user.cpp:30:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<g[nod].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:42:17: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if (i>>(n-1)&1==1) nextt=curent*2-(1<<n); else ^ user.cpp:45:17: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if (i>>(n-1)&1==1) nextt=curent*2-(1<<n)+1; else ^ user.cpp:36:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("biti.in","r",stdin); ^ user.cpp:37:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("biti.out","w",stdout); ^ user.cpp:38:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^