foo.cc: In function 'int main()':
foo.cc:12:9: error: expected ']' before numeric constant
   12 |  a[m + 2 2][m + 2 -2] = 0;
      |         ^~
      |         ]
foo.cc:12:9: error: expected ';' before numeric constant
   12 |  a[m + 2 2][m + 2 -2] = 0;
      |         ^~
      |         ;
foo.cc:12:10: warning: statement has no effect [-Wunused-value]
   12 |  a[m + 2 2][m + 2 -2] = 0;
      |  ~~~~~~~~^

Found 10 testcases.
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