foo.cc: In function 'int main()':
foo.cc:7:8: error: expected initializer before 'k'
  int n k;
        ^
foo.cc:8:9: error: 'n' was not declared in this scope
  cin >> n >> k;
         ^
foo.cc:8:14: error: 'k' was not declared in this scope
  cin >> n >> k;
              ^

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