Compilare: user.cpp: In function ‘int main()’: user.cpp:81:17: warning: unused variable ‘j’ [-Wunused-variable] long long k,q,i,j,l1,c1,l2,c2,sqq; ^ user.cpp: In function ‘long long int rec(long long int, long long int, long long int, long long int, long long int, long long int, long long int)’: user.cpp:77:5: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:79:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] {freopen ("tromino.in","r",stdin); ^ user.cpp:80:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("tromino.out","w",stdout); ^ user.cpp:82:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld",&k,&q); ^ user.cpp:93:47: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] {scanf("%lld%lld%lld%lld",&l1,&c1,&l2,&c2); ^