foo.cc: In function 'int main()':
foo.cc:6:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(a>b&&a<c||a<b&&a>c) cout<<a<<" ";
        ~~~^~~~~
foo.cc:7:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(b>a&&b<c||b<a&&b>c) cout<<b<<" ";
        ~~~^~~~~
foo.cc:8:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(c>b&&c<a||c<b&&c>a) cout<<c<<" ";
        ~~~^~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。