/in/p2.cpp: In function 'int tree_max(tree_t)':
/in/p2.cpp:178:89: error: too many arguments to function 'int max(int, int)'
         return max(tree_elt(tree), tree_max(tree_left(tree)), tree_max(tree_right(tree)));
                                                                                         ^
/in/p2.cpp:162:12: note: declared here
 static int max(int a,int b){
            ^~~