foo.cc: In function 'int main()':
foo.cc:12:13: error: array must be initialized with a brace-enclosed initializer
   12 |    int a[1]=1,a[2]=1,a[3]=2;
      |             ^
foo.cc:12:15: error: conflicting declaration 'int a [2]'
   12 |    int a[1]=1,a[2]=1,a[3]=2;
      |               ^
foo.cc:12:8: note: previous declaration as 'int a [1]'
   12 |    int a[1]=1,a[2]=1,a[3]=2;
      |        ^
foo.cc:12:22: error: conflicting declaration 'int a [3]'
   12 |    int a[1]=1,a[2]=1,a[3]=2;
      |                      ^
foo.cc:12:8: note: previous declaration as 'int a [1]'
   12 |    int a[1]=1,a[2]=1,a[3]=2;
      |        ^
foo.cc:9:6: warning: unused variable 'a' [-Wunused-variable]
    9 |  int a[y];
      |      ^

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