foo.c: In function 'main':
foo.c:7:17: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
    7 |         if(month<8&month!=2)
      |            ~~~~~^~
foo.c:10:19: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   10 |         if(month%2!=1&month!=2)
      |            ~~~~~~~^~~
foo.c:15:19: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   15 |         if(month%2!=1&month!=2)
      |            ~~~~~~~^~~
foo.c:19:26: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   19 |          else if(year%100==0&year%400!=0){printf("28");}
      |                  ~~~~~~~~^~~

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