foo.cc: In function 'int main()':
foo.cc:7:18: warning: comparison of constant '500' with boolean expression is always false [-Wbool-compare]
    7 |         if(1000>x>=500)
      |            ~~~~~~^~~~~
foo.cc:7:16: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
    7 |         if(1000>x>=500)
      |            ~~~~^~
foo.cc:11:23: warning: comparison of constant '1000' with boolean expression is always false [-Wbool-compare]
   11 |         else if(1500>x>=1000)
      |                 ~~~~~~^~~~~~
foo.cc:11:21: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   11 |         else if(1500>x>=1000)
      |                 ~~~~^~
foo.cc:15:23: warning: comparison of constant '1500' with boolean expression is always false [-Wbool-compare]
   15 |         else if(2000>x>=1500)
      |                 ~~~~~~^~~~~~
foo.cc:15:21: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   15 |         else if(2000>x>=1500)
      |                 ~~~~^~

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