Given a tree with n nodes, the points have power
Find the number of point pairs (x,y)
where x!=y , the difference between the maximum value and the minimum value on the path from x to y
Category: Mathematics
Applied Mathematics is a general term for mathematical theories and methods with a clear application purpose. The study of how to apply mathematical knowledge to the branches of mathematics in other categories (especially science) can be said to be the opposite of pure mathematics. Including differential equations, vector analysis, matrix, Fourier transform, complex analysis, numerical methods, probability theory, mathematical statistics, operations research, control theory, combinatorial mathematics, information theory and many other branches of mathematics, as well as from various application fields The study of the mathematical problem presented. Computational mathematics can sometimes be regarded as part of applied mathematics.
Leekcode solving record
There was a LeekCode competition last night. Five questions were solved in two and a half hours. After solving the first two questions easily, I got stuck on the third question. When there was half
2019 Introduction to the ACM Base of East China Jiaotong University
1. Introduction to the achievements of the base: ACM International Collegiate Programming Contest (ACM International Collegiate Programming Contest (referred to as ACM-ICPC or ICPC)) is organized b
101. Symmetrical binary tree
Given a binary tree, check whether it is mirror-symmetrical.
For example, the binary tree [1,2,2,3,4,4,3] is symmetrical.
1
/ \
2 2
/ \ / \
3 4 4 3
But the following (1,2,2,null,3,nu
2-2 Numpy-Matrix
1 # !usr/bin/env python
2 # Author:@vilicute
3
4 import numpy as np
5 # Creation of matrix
6 matr1 = np.mat(“4 2 3;4 5 6;7 8 9” )
7 matr2 = np.matrix([[4,5,6],[7,8,9],[1 ,2,3]])
8 pri
2019.9.26 – Implementation code of the binary tree
# coding:utf-8
class Node(object):
“”””””
def __init__(self, item):
self. elem = item
self,lchild = None
self.rchild = None
class Tree(object):
“””Binary Tree”””
def __init__(sel
144. Pre-sequence traversal of the binary tree
Given a binary tree, return its previous traversal.
Example:
Input: [1,null,2,3]
1
\
2
/
3 Output: [1,2,3]
Advanced: The recursive algorithm is very simple, can you do it through