e_flag;
int idx = Min2k; //从上往下搜索，先定位根节点
for (int k = idx / 2u; k > 0; k /= 2u) {
int t = info[idx];
if (n <= info[idx]) { info[idx] -= erase_flag; idx -= k;} //进入左子树
else {
n -= t;
if (Total != Min2k && Total != Min2k - 1) //若不是完全二叉树
while (idx + k > Total)