/in/foo.cc: In function 'void solve()':
/in/foo.cc:28:5: error: 'cout' was not declared in this scope
     cout<<tot<<endl;
     ^~~~
/in/foo.cc:28:16: error: 'endl' was not declared in this scope
     cout<<tot<<endl;
                ^~~~
/in/foo.cc: In function 'void DP()':
/in/foo.cc:56:5: error: 'cout' was not declared in this scope
     cout<<ans<<endl;
     ^~~~
/in/foo.cc:56:16: error: 'endl' was not declared in this scope
     cout<<ans<<endl;
                ^~~~