牛客OJ：判断子结构和子树

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/ShellDawn/article/details/89069722

判断子结构：

class Solution {
public:
    bool solve(TreeNode* a, TreeNode* b){
        if(b == NULL) return true;
        if(a == NULL) return false;
        if(a->val == b->val){
            return 
                solve(a->left,b->left)
                && 
                solve(a->right,b->right);
        }
        return false;
    }
    bool judge(TreeNode* a,TreeNode* b){
        if(a == NULL || b == NULL) return false;
        bool ans = false;
        if(a->val == b->val) ans = (ans || solve(a,b));
        if(ans) return true;
        ans = (ans || judge(a->left,b));
        ans = (ans || judge(a->right,b));
        return ans;
    }
    bool HasSubtree(TreeNode* pRoot1, TreeNode* pRoot2)
    {
        return judge(pRoot1,pRoot2);
    }
};

判断子树：

bool solve(TreeNode* a, TreeNode* b){
    if(a == NULL && b == NULL) return true;
    if(a == NULL || b == NULL) return false;
    if(a->val == b->val){
        return 
            solve(a->left,b->left)
            && 
            solve(a->right,b->right);
    }
    return false;
}
bool judge(TreeNode* a,TreeNode* b){
    if(a == NULL || b == NULL) return false;
    bool ans = false;
    if(a->val == b->val) ans = (ans || solve(a,b));
    if(ans) return true;
    ans = (ans || judge(a->left,b));
    ans = (ans || judge(a->right,b));
    return ans;
}
bool HasSubtree(TreeNode* pRoot1, TreeNode* pRoot2)
{
    return judge(pRoot1,pRoot2);
}