#include <iostream>
#include <string>
#include <vector>
#include <queue>
using namespace std;
struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode() : val(0), left(nullptr), right(nullptr) {}
    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
    TreeNode(int x, TreeNode* left, TreeNode* right) : val(x), left(left), right(right) {}
};

int findBottomLeftValue(TreeNode* root) {
    queue<TreeNode*>q;
    int number = 0;
    if (root)
    {
        q.push(root);
        number = 1;
    }
    vector<vector<int>> vv;
    while (!q.empty())
    {
        vector<int>v;
        for (int i = 0; i < number; ++i)
        {
            TreeNode* front = q.front();
            v.push_back(front->val);
            if (front->left)
                q.push(front->left);
            if (front->right)
                q.push(front->right);
            q.pop();
        }
        vv.push_back(v);
        number = q.size();
    }
    int row = vv.size();
    return vv[row][0];
}

int main()
{
    TreeNode* n1 = new TreeNode(1);
    TreeNode* n2 = new TreeNode(2);
    TreeNode* n3 = new TreeNode(3);
    TreeNode* n4 = new TreeNode(4);
    TreeNode* n5 = new TreeNode(5);
    TreeNode* n6 = new TreeNode(6);
    TreeNode* n7 = new TreeNode(7);
    n1->left = n2;
    n1->right = n3;
    n2->left = n4;
    n3->left = n5;
    n3->right = n6;
    n5->left = n6;

    findBottomLeftValue(n1);
    return 0;
}


/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
// *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
// *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
// *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
// * };
// */
//class Solution {
//
//public:
//    vector<int> largestValues(TreeNode* root) {
//        queue<TreeNode*> q;
//        size_t levelSize = 0;
//        if (root)
//        {
//            q.push(root);
//            levelSize = 1;
//        }
//        vector<vector<int>> vv;
//        while (!q.empty())
//        {
//            vector<int>v;
//            for (int i = 0; i < levelSize; ++i)
//            {
//                TreeNode* front = q.front();
//                v.push_back(front->val);
//                if (front->left)
//                    q.push(front->left);
//                if (front->right)
//                    q.push(front->right);
//                q.pop();
//            }
//            vv.push_back(v);
//            //当前层出完了，下一层也都进入，更改levelSize
//            levelSize = q.size();
//        }
//        vector<int> ret;
//        for (size_t i = 0; i < vv.size(); i++)
//        {
//            int max = vv[i][0];
//            for (size_t j = 0; j < vv[i].size(); j++)
//            {
//                if (max < vv[i][j])
////                {
////                    max = vv[i][j];
////                }
////            }
////            ret.push_back(max);
////        }
////        return ret;
//
//
//
//
//    }
//};
////#include <iostream>
////#include <string>
////using namespace std;
////
////
////string replaceSpaces(string s, int length) {
////    string str(s, length);
////    string ret;
////    int sz = str.size();
////    for (auto& e : str)
////    {
////        if (e == ' ')
////        {
////            ret += "%20";
////        }
////        else
////        {
////            ret += e;
////        }
////    }
////    int diff = length - sz;
////    while (diff--)
//    {
//        ret += "%20";
//    }
//    return ret;
//}
//#include<vector>
//
//int main() {
//    
//    vector<int> a = { 1,2,3,4,5 };
//
//    auto e=a.erase(a.begin());
//
//
//    int n=0;
//    //cin >> n;
//    //while (n--)
//    //{
//    //    getline(cin, str,'\n');
//    //    if (str.size() <= 10)
//    //    {
//    //        cout << str << endl;
//    //    }
//    //    else
//    //    {
//    //        size_t len = str.size();
//    //        len -= 2;
//    //        cout << str[0] << len << str[str.size() - 1] << endl;
//    //    }
//    //}
//    return 0;
//}
//// 64 位输出请用 printf("%lld")
////#include <stdio.h>
////#include<string.h>
////#include<stdio.h>
////char* f(char* str, char ch)
////{
////	char* it1 = str;
////	char* it2 = str;
////	while (*it2 != '\0')
////	{
////		while (*it2 == ch)
////		{
////			it2++;
////		}
////		*it1++ = *it2++;
////	}
////	return str;
////}
////int main() {
////	char a[10];
////	strcpy(a, "abcdcccd");
////	printf("%s", f(a, 'c'));
////	return 0;
////}
//////int main()
//////{
//////	char p1[15] = "abcd", p2[] = "ABCD", str[50] = "xyz";
//////	strcpy(str + 2, strcat(p1 + 2, p2 + 1));
//////	printf("%s", str);
//////	return 0;
//////}
////
//////int main()
//////{
//////
//////	char a[] = "abcd";
//////	char* p = a;
//////	char ch = (*p)++;
//////	printf("%c\n", ch);
//////	printf("%s", a);
//////
//////	//const char* str[3] = { "stra", "strb", "strc" };
//////	//const char* p = str[0];
//////	//int i = 0;
//////	//while (i < 3)
//////	//{
//////	//	printf("%s ", p++);
//////	//	i++;
//////	//}
//////	return 0;
//////}