View Compilation Error

0_0_38566208_11478.cpp: In function 'int main()':
0_0_38566208_11478.cpp:9:5: error: 'cin' was not declared in this scope
    9 |     cin>>cas;
      |     ^~~
0_0_38566208_11478.cpp:3:1: note: 'std::cin' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
    2 | #include<algorithm>
  +++ |+#include <iostream>
    3 | using namespace std;
0_0_38566208_11478.cpp:45:9: error: 'cout' was not declared in this scope
   45 |         cout<<maxn<<endl;
      |         ^~~~
0_0_38566208_11478.cpp:45:9: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
0_0_38566208_11478.cpp:45:21: error: 'endl' was not declared in this scope
   45 |         cout<<maxn<<endl;
      |                     ^~~~
0_0_38566208_11478.cpp:3:1: note: 'std::endl' is defined in header '<ostream>'; did you forget to '#include <ostream>'?
    2 | #include<algorithm>
  +++ |+#include <ostream>
    3 | using namespace std;