View Compilation Error

0_0_19243463_22249.cpp: In function 'int main()':
0_0_19243463_22249.cpp:6:15: error: conflicting declaration 'int a [1000]'
     int a[1000]={0};
               ^
0_0_19243463_22249.cpp:5:13: note: previous declaration as 'int a'
     int N,i,a,sum;
             ^
0_0_19243463_22249.cpp:14:22: error: invalid types 'int[int]' for array subscript
       scanf("%d",&a[i]);
                      ^
0_0_19243463_22249.cpp:15:18: error: invalid types 'int[int]' for array subscript
       sum=sum+a[i];
                  ^