foo.cc: In function 'int main()':
foo.cc:14:31: warning: left operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                          ~~~~~^~~
foo.cc:14:37: warning: right operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                                     ^
foo.cc:14:39: warning: right operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                                       ^
foo.cc:14:41: warning: right operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                                         ^
foo.cc:14:43: warning: right operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                                           ^~
foo.cc:14:46: warning: right operand of comma operator has no effect [-Wunused-value]
   14 |                 else if (month==1,3,5,7,8,10,12)
      |                                              ^~
foo.cc:30:32: warning: left operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                          ~~~~~~^~~~
foo.cc:30:41: warning: right operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                                         ^
foo.cc:30:44: warning: right operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                                            ^
foo.cc:30:47: warning: right operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                                               ^
foo.cc:30:50: warning: right operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                                                  ^~
foo.cc:30:54: warning: right operand of comma operator has no effect [-Wunused-value]
   30 |                 else if (month == 1, 3, 5, 7, 8, 10, 12)
      |                                                      ^~

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