View Compilation Error

0_0_36863781_11156.cpp: In function 'int main()':
0_0_36863781_11156.cpp:6:9: error: 'i' was not declared in this scope
   int a[i],sum=0;
         ^
0_0_36863781_11156.cpp:8:18: error: invalid types 'int[int]' for array subscript
   scanf("%d",&a[i]);
                  ^
0_0_36863781_11156.cpp:9:11: error: invalid types 'int[int]' for array subscript
   sum+=a[i];
           ^
0_0_36863781_11156.cpp:12:17: error: 'sum' was not declared in this scope
   printf("%d\n",sum);
                 ^
0_0_36863781_11156.cpp: At global scope:
0_0_36863781_11156.cpp:14:2: error: expected unqualified-id before 'return'
  return 0;
  ^
0_0_36863781_11156.cpp:15:2: error: expected declaration before '}' token
  }
  ^