/in/foo.cc: In function 'int main()':
/in/foo.cc:16:12: warning: comparison of constant '10' with boolean expression is always true [-Wbool-compare]
     if(1<=x<10)
        ~~~~^~~
/in/foo.cc:16:9: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
     if(1<=x<10)
        ~^~~
/in/foo.cc:20:13: warning: comparison of constant '15' with boolean expression is always true [-Wbool-compare]
     if(10<=x<15)
        ~~~~~^~~
/in/foo.cc:20:10: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
     if(10<=x<15)
        ~~^~~
/in/foo.cc:24:13: warning: comparison of constant '30' with boolean expression is always true [-Wbool-compare]
     if(15<=x<30)
        ~~~~~^~~
/in/foo.cc:24:10: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
     if(15<=x<30)
        ~~^~~