Compilare: user.cpp: In function ‘void backs(int, int)’: user.cpp:24:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<k[p].size();i++) ^ user.cpp:27:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<k[p].size();i++) ^ user.cpp: In function ‘void backs2(int, int)’: user.cpp:55:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<k[p].size();i++) ^ user.cpp:58:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<k[p].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:81:38: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if (i!=2&&i!=3&&i!=5&&i!=7&&i!=11&i!=13&&i!=17&&i!=19&&i!=23&&i!=29&&i!=31) ^ user.cpp:70:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numerologie.in","r",stdin); ^ user.cpp:71:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numerologie.out","w",stdout); ^ user.cpp:72:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^