foo.cc: In function 'int main()':
foo.cc:7:12: warning: comparison of constant '15' with boolean expression is always true [-Wbool-compare]
    if(-15<n<15)
       ~~~~~^~~
foo.cc:7:10: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
    if(-15<n<15)
       ~~~^~

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