foo.cc: In function 'int main()':
foo.cc:11:21: warning: comparison of constant '10' with boolean expression is always false [-Wbool-compare]
   11 |         else if(1<=a>10)
      |                 ~~~~^~~
foo.cc:11:18: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   11 |         else if(1<=a>10)
      |                 ~^~~
foo.cc:15:22: warning: comparison of constant '15' with boolean expression is always false [-Wbool-compare]
   15 |         else if(10<=a>15)
      |                 ~~~~~^~~
foo.cc:15:19: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   15 |         else if(10<=a>15)
      |                 ~~^~~
foo.cc:19:22: warning: comparison of constant '30' with boolean expression is always false [-Wbool-compare]
   19 |         else if(15<=a>30)
      |                 ~~~~~^~~
foo.cc:19:19: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   19 |         else if(15<=a>30)
      |                 ~~^~~

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