Compilare: user.cpp: In function ‘int main()’: user.cpp:89:53: warning: operation on ‘nr2[i]’ may be undefined [-Wsequence-point] M[i][++nr2[i]]=(1LL)*M[i][nr2[i]-1]*b[i]; ^ user.cpp:69:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cumpanit.in","r",stdin); ^ 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 ("cumpanit.out","w",stdout); ^ user.cpp:71:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lld %lld", &c, &d); ^