foo.cc: In function 'int maincx()':
foo.cc:3:9: error: 'cin' was not declared in this scope
    3 |         cin>>n>>k;
      |         ^~~
foo.cc:3:14: error: 'n' was not declared in this scope
    3 |         cin>>n>>k;
      |              ^
foo.cc:3:17: error: 'k' was not declared in this scope
    3 |         cin>>n>>k;
      |                 ^
foo.cc:6:22: error: 'm' was not declared in this scope
    6 |                 cin>>m;
      |                      ^
foo.cc:7:17: error: 'a' was not declared in this scope
    7 |                 a[m]++;
      |                 ^
foo.cc:8:10: error: 'm' was not declared in this scope
    8 |         }m=0;
      |          ^
foo.cc:11:20: error: 'a' was not declared in this scope
   11 |                 if(a[i]>0) m++;
      |                    ^
foo.cc:14:25: error: 'cout' was not declared in this scope
   14 |                         cout<<i;
      |                         ^~~~
foo.cc:15:25: error: return-statement with no value, in function returning 'int' [-fpermissive]
   15 |                         return;
      |                         ^~~~~~
foo.cc:18:9: error: 'cout' was not declared in this scope
   18 |         cout<<"NO RESULT";
      |         ^~~~
foo.cc:19:1: warning: control reaches end of non-void function [-Wreturn-type]
   19 | }
      | ^

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