foo.cc: In function 'int main()':
foo.cc:6:6: warning: left operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |     ~^~~
foo.cc:6:12: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |            ^
foo.cc:6:14: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |              ^
foo.cc:6:16: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |                ^
foo.cc:6:18: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |                  ^~
foo.cc:6:21: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |  if(x==1,3,5,7,8,10,12)
      |                     ^~
foo.cc:8:6: warning: left operand of comma operator has no effect [-Wunused-value]
    8 |  if(x==4,6,9,11)
      |     ~^~~
foo.cc:8:12: warning: right operand of comma operator has no effect [-Wunused-value]
    8 |  if(x==4,6,9,11)
      |            ^
foo.cc:8:14: warning: right operand of comma operator has no effect [-Wunused-value]
    8 |  if(x==4,6,9,11)
      |              ^~

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