foo.cc: In function 'int main()':
foo.cc:7:50: error: lvalue required as left operand of assignment
    7 |  if(a=1 || a=3 || a=5 || a=7 || a=8 || a=10 || a=12)
      |                                                  ^~
foo.cc:9:28: error: lvalue required as left operand of assignment
    9 |  if(a=4 || a=6 || a=9 || a=11)
      |                            ^~
foo.cc:11:6: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   11 |  if(a=2)
      |     ~^~

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