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Procedural programming in C About the tutorial This tutorial is about procedural programming in C. We are going to use gcc within a linux environment to compile and run our programs. If you don’t want to install any compilers on the computer, you can use an online compiler like repl.it, or onlinegdb. Understanding the basics What is C? C is a general-purpose, procedural computer programming language supporting structured programming, lexical variable scope, and recursion, with a static type system. By design, C provides constructs that map efficiently to typical machine instructions. It has found lasting use in applications previously coded in assembly language. Such applications include operating systems and various application software for computer architectures that range from supercomputers to PLCs and embedded systems. ...

Autodesk Fusion and CAM Introduction Fusion 360 is a computer aided design (CAD) and computer aided manufacturing (CAM) software developed by Autodesk. Significance of G and M codes G and M codes are the most common codes used in CNC machines. G codes are used to control the movement of the machine and M codes are used to control the machine’s functions. Using Fusion for CAM Open fusion and create a new design. Machine setup Every machine has a different setup, different table sizes and different work holding methods. Fusion 360 allows you to define the machine setup and the work holding method you will be using. ...

X.509 is a standard that defines the format of public key certificates. These certificates are used in many Internet protocols, including TLS and SSL, which are the basis for HTTPS, the secure protocol for browsing the web. They’re also used for securing communications in 5G networks.

Leetcode solutions Problem 1: Two Sum 1 2 3 4 5 6 7 8 9 10 11 12 class Solution(object): def twoSum(self, nums, target): """ :type nums: List[int] :type target: int :rtype: List[int] """ for i in range(0, len(nums)): for j in range(0, len(nums)): if nums[i]+nums[j] == target and i!=j: op = [i,j] return op Problem 2: Roman to integer 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 class Solution(object): def romanToInt(self, s): """ :type s: str :rtype: int """ roman = {'I':1,'V':5,'X':10,'L':50,'C':100,'D':500,'M':1000,'IV':4,'IX':9,'XL':40,'XC':90,'CD':400,'CM':900} i = 0 num = 0 while i < len(s): if i+1<len(s) and s[i:i+2] in roman: num+=roman[s[i:i+2]] i+=2 else: #print(i) num+=roman[s[i]] i+=1 return num Problem 3: Pallindrome 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 class Solution(object): def isPalindrome(self, x): """ :type x: int :rtype: bool """ if x < 0: return False # Store the number in a variable number = x # This will store the reverse of the number reverse = 0 while number: reverse = reverse * 10 + number % 10 number //= 10 return x == reverse Problem 4: Longest Common Prefix 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 class Solution(object): def longestCommonPrefix(self, strs): """ :type strs: List[str] :rtype: str """ size = len(strs) # if size is 0, return empty string if (size == 0): return "" if (size == 1): return strs[0] # sort the array of strings strs.sort() # find the minimum length from # first and last string end = min(len(strs[0]), len(strs[size - 1])) # find the common prefix between # the first and last string i = 0 while (i < end and strs[0][i] == strs[size - 1][i]): i += 1 pre = strs[0][0: i] return pre Problem 5: Valid Parentheses 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 class Solution(object): def isValid(self, s): """ :type s: str :rtype: bool """ # Stack for left symbols leftSymbols = [] # Loop for each character of the string for c in s: # If left symbol is encountered if c in ['(', '{', '[']: leftSymbols.append(c) # If right symbol is encountered elif c == ')' and len(leftSymbols) != 0 and leftSymbols[-1] == '(': leftSymbols.pop() elif c == '}' and len(leftSymbols) != 0 and leftSymbols[-1] == '{': leftSymbols.pop() elif c == ']' and len(leftSymbols) != 0 and leftSymbols[-1] == '[': leftSymbols.pop() # If none of the valid symbols is encountered else: return False return leftSymbols == [] Problem 6: Largest Substring Between Two Equal Characters 1 2 3 4 5 6 7 8 class Solution: def maxLengthBetweenEqualCharacters(self, s: str) -> int: output = -1 for i in range (0, len(s)): for j in range (i+1, len(s)): if s[i] == s[j]: output = max(output, j-i-1) return output

Operating systems Bases of an operating system Execute user programs and make solving user problems easier Make the computer system convenient to use Use the computer hardware in an efficient manner A computer system can be divided roughly into four components: the hardware, the operating system, the application programs, and the users. Use of an operating system The operating system is responsible for the following activities in connection with process management Process creation and deletion Process suspension and resumption Provision of mechanisms for process synchronization Provision of mechanisms for process communication Provision of mechanisms for deadlock handling Operating systems is a resource allocator and it is a control program. ...