imagine.cpp:4: error: 'mt19937_64' does not name a type imagine.cpp: In function 'long long int val(bool)': imagine.cpp:7: error: 'rnd' was not declared in this scope imagine.cpp: In function 'int bruteforce()': imagine.cpp:31: warning: no return statement in function returning non-void imagine.cpp: In function 'int efficient()': imagine.cpp:37: warning: no return statement in function returning non-void imagine.cpp: In function 'int main()': imagine.cpp:48: error: 'random_device' is not a member of 'std' imagine.cpp:48: error: expected ',' or ';' before '{' token imagine.cpp:48: error: expected primary-expression before ')' token imagine.cpp:49: error: 'rnd' was not declared in this scope