foo.cc: In function 'int main()':
foo.cc:13:9: warning: comparison of constant '10' with boolean expression is always true [-Wbool-compare]
  if(0<=x<10)
     ~~~~^~~
foo.cc:13:6: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
  if(0<=x<10)
     ~^~~
foo.cc:17:10: warning: comparison of constant '25' with boolean expression is always true [-Wbool-compare]
  if(10<=x<25)
     ~~~~~^~~
foo.cc:17:7: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
  if(10<=x<25)
     ~~^~~

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