View Compilation Error

0_0_37835978_31947.cpp: In function 'void solve()':
0_0_37835978_31947.cpp:42:5: error: 'cin' was not declared in this scope
     cin >> n;
     ^
0_0_37835978_31947.cpp:56:5: error: 'cout' was not declared in this scope
     cout << ans << endl;
     ^
0_0_37835978_31947.cpp:56:20: error: 'endl' was not declared in this scope
     cout << ans << endl;
                    ^
0_0_37835978_31947.cpp: In function 'int main()':
0_0_37835978_31947.cpp:61:5: error: 'ios' has not been declared
     ios::sync_with_stdio(0),cin.tie(0);
     ^
0_0_37835978_31947.cpp:61:29: error: 'cin' was not declared in this scope
     ios::sync_with_stdio(0),cin.tie(0);
                             ^
0_0_37835978_31947.cpp:65:5: error: 'please' was not declared in this scope
     please ac;
     ^