View Compilation Error

0_0_28710461_24143.cpp: In function 'int main()':
0_0_28710461_24143.cpp:3:14: error: 'MAX' was not declared in this scope
  int n, i, a[MAX];
              ^
0_0_28710461_24143.cpp:6:3: error: 'a' was not declared in this scope
   a[i] = i;
   ^
0_0_28710461_24143.cpp:8:22: error: 'scanf' was not declared in this scope
  while (scanf("%d",&n)!=EOF)
                      ^
0_0_28710461_24143.cpp:8:25: error: 'EOF' was not declared in this scope
  while (scanf("%d",&n)!=EOF)
                         ^
0_0_28710461_24143.cpp:16:5: error: 'a' was not declared in this scope
     a[i] = a[i - 1] + a[i - 3];
     ^
0_0_28710461_24143.cpp:19:17: error: 'a' was not declared in this scope
   printf("%d\n",a[n]);
                 ^
0_0_28710461_24143.cpp:19:21: error: 'printf' was not declared in this scope
   printf("%d\n",a[n]);
                     ^