procedure Solve(pre,mid:string); |
var i:integer; |
begin |
if (pre='''') or (mid='''') then exit; |
i:=pos(pre[1],mid); |
solve(copy(pre,2,i),copy(mid,1,i-1)); |
solve(copy(pre,i+1,length(pre)-i),copy(mid,i+1,length(mid)-i)); |
post:=post+pre[1]; {加上根,递归结束后post即为后序遍历} |
end; |