foo.cc: In function 'int main()':
foo.cc:10:6: error: conflicting declaration 'int a [1]'
   10 |  int a[1]=1,a[2]=1,a[3]=2;
      |      ^
foo.cc:9:6: note: previous declaration as 'int a [y]'
    9 |  int a[y];
      |      ^
foo.cc:10:13: error: conflicting declaration 'int a [2]'
   10 |  int a[1]=1,a[2]=1,a[3]=2;
      |             ^
foo.cc:9:6: note: previous declaration as 'int a [y]'
    9 |  int a[y];
      |      ^
foo.cc:10:20: error: conflicting declaration 'int a [3]'
   10 |  int a[1]=1,a[2]=1,a[3]=2;
      |                    ^
foo.cc:9:6: note: previous declaration as 'int a [y]'
    9 |  int a[y];
      |      ^

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