foo.cc: In function 'int main()':
foo.cc:3:5: error: 'cin' was not declared in this scope
    3 |     cin >> n >> k;
      |     ^~~
foo.cc:3:12: 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:5:16: error: 'a' was not declared in this scope
    5 |         cin >> a[i];
      |                ^
foo.cc:7:10: error: 'f' was not declared in this scope
    7 |     fill(f, f + N, INF);
      |          ^
foo.cc:7:17: error: 'N' was not declared in this scope
    7 |     fill(f, f + N, INF);
      |                 ^
foo.cc:7:20: error: 'INF' was not declared in this scope
    7 |     fill(f, f + N, INF);
      |                    ^~~
foo.cc:7:5: error: 'fill' was not declared in this scope
    7 |     fill(f, f + N, INF);
      |     ^~~~
foo.cc:10:13: error: 'a' was not declared in this scope
   10 |         if (a[i] < a[k])
      |             ^
foo.cc:11:15: error: 'lower_bound' was not declared in this scope
   11 |             f[lower_bound(f, f + n, a[i]) - f] = a[i];
      |               ^~~~~~~~~~~
foo.cc:12:17: error: 'lower_bound' was not declared in this scope
   12 |     int l_max = lower_bound(f, f + n, INF) - f;
      |                 ^~~~~~~~~~~
foo.cc:17:13: error: 'a' was not declared in this scope
   17 |         if (a[k] < a[i])
      |             ^
foo.cc:21:5: error: 'cout' was not declared in this scope
   21 |     cout << l_max + 1 + r_max << endl;
      |     ^~~~
foo.cc:21:34: error: 'endl' was not declared in this scope
   21 |     cout << l_max + 1 + r_max << endl;
      |                                  ^~~~

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