View Compilation Error

0_0_33007533_22527.cpp: In function 'int main()':
0_0_33007533_22527.cpp:23:3: error: 'cin' was not declared in this scope
   cin>>n>>m;;
   ^
0_0_33007533_22527.cpp:37:4: error: 'cout' was not declared in this scope
    cout<<ans<<endl;
    ^
0_0_33007533_22527.cpp:37:10: error: 'ans' was not declared in this scope
    cout<<ans<<endl;
          ^
0_0_33007533_22527.cpp:37:15: error: 'endl' was not declared in this scope
    cout<<ans<<endl;
               ^