View Compilation Error

0_0_39369207_3545.cpp:9:1: error: 'map' does not name a type
    9 | map <int,int> f;
      | ^~~
0_0_39369207_3545.cpp: In function 'int main()':
0_0_39369207_3545.cpp:33:9: error: 'sort' was not declared in this scope; did you mean 'short'?
   33 |         sort(a + 1,a + n + 1,cmp);
      |         ^~~~
      |         short
0_0_39369207_3545.cpp:35:13: error: 'f' was not declared in this scope
   35 |             f[i] = a[i].z;
      |             ^
0_0_39369207_3545.cpp:40:49: error: 'f' was not declared in this scope
   40 |         for(int i = 1;i <= n;i++) ans = max(ans,f[i]);
      |                                                 ^