阿里巴巴2014筆試演算法題匯總

bool IsSubtree(BinaryTreeNode* pRoot1, BinaryTreeNode* pRoot2) {      if (pRoot1 == NULL || pRoot2 == NULL) {          return false;      }      stack<BinaryTreeNode*> stk;      stk.push(pRoot1);      while (!stk.empty()) {          BinaryTreeNode *tmp = stk.top();          stk.pop();          if (tmp->m_nValue == pRoot2->m_nValue) {              stack<BinaryTreeNode*> first;              BinaryTreeNode *f;              stack<BinaryTreeNode*> second;              BinaryTreeNode *s;              first.push(tmp);              second.push(pRoot2);              bool find = true;              while (!first.empty()) {                  f = first.top();                  first.pop();                  s = second.top();                  second.pop();                  if (f->m_nValue != s->m_nValue) {                      find = false;                      break;                  }                  if (s->m_pLeft != NULL) {                      if (f->m_pLeft == NULL) {                          find = false;                          break;                  } else {                          first.push(f->m_pLeft);                          second.push(s->m_pLeft);                      }                  }                  if (s->m_pRight != NULL) {                      if (f->m_pRight == NULL) {                          find = false;                          break;                  } else {                          first.push(f->m_pRight);                          second.push(s->m_pRight);                      }                  }              }              if (find == true && first.empty()) {                  return true;              }          }          if (tmp->m_pLeft != NULL) {              stk.push(tmp->m_pLeft);          }          if (tmp->m_pRight != NULL) {              stk.push(tmp->m_pRight);          }      }      return false;  }  

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