foo.cc: In function 'int main()':
foo.cc:8:7: error: 'x' was not declared in this scope
    8 |  cin>>x>>y;
      |       ^
foo.cc:12:12: error: expected initializer before '==' token
   12 |    int a[1]==1,a[2]==1,a[3]==2;
      |            ^~

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