View Compilation Error

0_0_39382128_16573.cpp: In function 'int main()':
0_0_39382128_16573.cpp:4:11: error: 'cin' was not declared in this scope
    4 |     while(cin>>a>>b){
      |           ^~~
0_0_39382128_16573.cpp:10:13: error: 'cout' was not declared in this scope
   10 |             cout<<d<<endl;
      |             ^~~~
0_0_39382128_16573.cpp:10:22: error: 'endl' was not declared in this scope
   10 |             cout<<d<<endl;
      |                      ^~~~