foo.cpp:1:1: error: 'include' does not name a type
 include<iostream>
 ^~~~~~~
foo.cpp: In function 'int main()':
foo.cpp:8:1: error: 'cin' was not declared in this scope
 cin>>a[i];
 ^~~
foo.cpp:9:1: error: 'cin' was not declared in this scope
 cin>>n;
 ^~~
foo.cpp:15:1: error: 'cout' was not declared in this scope
 cout<<k;
 ^~~~
foo.cpp:6:7: warning: unused variable 'j' [-Wunused-variable]
 int i,j,k=0,n;
       ^