foo.cc: In function 'int main()':
foo.cc:5:17: error: expected ']' before ';' token
    5 |         cin>>a[1;>>a[2]>>a[3]
      |                 ^
      |                 ]
foo.cc:5:18: error: expected primary-expression before '>>' token
    5 |         cin>>a[1;>>a[2]>>a[3]
      |                  ^~

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