/in/foo.cc: In function 'int main()':
/in/foo.cc:45:31: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(opt[i]==">="||opt[i]==">"&&c1==0)c1++,xb1=i;
                    ~~~~~~~~~~~^~~~~~~
/in/foo.cc:46:36: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   else if(opt[i]=="<="||opt[i]=="<"&&c2==0)c2++,xb2=i;
                         ~~~~~~~~~~~^~~~~~~
/in/foo.cc:52:19: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(opt[i]==">="&&opt[j]==">="||opt[i]==">"&&opt[j]==">")
       ~~~~~~~~~~~~^~~~~~~~~~~~~~
/in/foo.cc:55:20: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(opt[i]=="<="&&opt[j]=="<="||opt[i]=="<"&&opt[j]=="<")
        ~~~~~~~~~~~~^~~~~~~~~~~~~~
/in/foo.cc: In function 'int answer(std::__cxx11::string, int, char, std::__cxx11::string&)':
/in/foo.cc:30:9: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return ret;
         ^~~