View Compilation Error

0_0_30835939_11390.cpp: In function 'int is(int)':
0_0_30835939_11390.cpp:5:6: error: 'i' was not declared in this scope
  if (i >= n) return 1;
      ^
0_0_30835939_11390.cpp: In function 'int main()':
0_0_30835939_11390.cpp:14:19: error: 'ispure' was not declared in this scope
     if (ispure(n-i) == 1)
                   ^