Compilare: main.cpp:3: warning: ignoring '#pragma optimize GCC' [-Wunknown-pragmas] 3 | #pragma optimize GCC ("Ofast") | main.cpp: In function 'bool valid(long long unsigned int, long long unsigned int)': main.cpp:46:20: warning: comparison of integer expressions of different signedness: 'long long unsigned int' and 'int' [-Wsign-compare] 46 | for(mask=1;mask<(1<<n);mask++) | ~~~~^~~~~~~ main.cpp:44:18: warning: unused variable 'j' [-Wunused-variable] 44 | int n,mask,i,j,s=x; | ^