digi calc

PHP//PHP Policy Mode Interfacemath{ Public functionCalc$op 1,$op 2); } classMathaddImplementsmath{ Public functionCalc$op 1,$op 2){ return $op 1+$op 2; } } classMathsubImplementsmath{ Public functionCalc$op 1,$op 2){ return $op 1-$op 2; } } classMathmulImplementsmath{ Public functionCalc$op 1,$op 2){ return $op 1*$op 2; } } classMathdivImplementsmath{ Public functionCalc$op 1,$op 2){

are inappropriate, as shown above, there will be an error!The reasons are explained as follows:When the Python function is defined, the value of the default parameter is L calculated, that is [] , because the default parameter L is also a variable, which points to the object [] , each time the function is called, if the change L of content, the next call, the contents of the default parameters will change, is no longer the function definition [] .Replace the above [] with none for this immutabl

Multi-state computer program, multi-state computer 1. Create a form 2. Create an Operator class with two operands and a method Public abstract class Operator {public abstract int Calc (); // Number of computations public int NumLeft {get; set;} public int NumRight {get; set ;}} 3. Create an Add class public class Add:Operator { public override int Calc() { return this.NumLeft +

foo ():Name= ' LHF 'def bar ():Name= ' Wupeiqi 'def TT ():Print (name)Return TTReturn bar25Func=foo ()Func () ()Eight recursionInside a function, you can call other functions. If a function calls itself internally, the function is a recursive function.1 def Calc (n):2 print (n)3 if int (N/2) ==0:4 return N5 Return Calc (int (N/2))67 Calc (10)89 Output:10 1011 51

returns the result as soon as it encounters a return statement, so can also be understood as a return statement that represents the end of the function If return is not specified in the function, the return value of this function is None V. RecursionInside a function, you can call other functions. If a function calls itself internally, the function is a recursive function.Def calc (n): print (n) if int (N/2) ==0: return n ret

parameters are also pitfall. Let's look at the following code. First define a list, add an end, and then return: def add_end(L=[]): L.append('END') return L Check the call result: >>> add_end([1, 2, 3])[1, 2, 3, 'END']>>> add_end(['x', 'y', 'z'])['x', 'y', 'z', 'END']>>> add_end()['END']>>> add_end()['END', 'END']>>> add_end()['END', 'END', 'END'] Here, we need to explain that when a Python function is defined, the value of the default parameter L is calculated, that is, []. L points to []. S

sequence, but this function must receive two functions. Reduce then applies the function to the results of the first two parameters and the elements of the next sequence. The following uses Reduce to implement a sequence summation operation. See the following example: def add(x,y): return x+yr=reduce(add, [1,2,3,4,5])print(r)E:\Study\python>python hello_python.py15 Its lambda version is: r=reduce(lambda x,y:x+y, [1,2,3,4,5]) Iv. Return Functions As mentioned above, a function can be assigne

parameters, tangible parameters and argumentsFormal parameters:Parametric the memory unit is allocated only when called, releasing the allocated memory unit immediately at the end of the call. Therefore, the formal parameter is only valid inside the function.Actual parameters:Arguments can be constants, variables, expressions, functions, and so on, regardless of the type of argument, and when a function call is made, they must have a definite value in order to pass these values to the parameter

Service Provider Interfaces Services provides discovery, dynamic replacement of discovery mechanisms Example: An interface: Public Interface Calc { Logger Logger = Loggerfactory.getlogger (Calc.class); Object Calc (int calctype);}Two implementations:To calculate the sin value: Public class Implements Calc { @Override Public Object

Take a look at the code first:Def calc (A, B): res = A/b return resdef main (): Money = input (' Enter how much: ') month = input (' Also several months: ') res = calc (int (money), Int (month)) return resMain ()When you run the Money input 10,month enter 0 to see the results:Run when money input Aa,month input HHH, view results: HHHIn the process of running, we need to process the excepti

)print("在外面看看name改了么?",name)输出 before change: stoneafter change: hello在外面看看name改了么? stoneSummary of 2.7.2, global and local variables:A variable defined in a subroutine is called a local variable, and a variable defined at the beginning of the program is called a global variable.The global variable scope is the entire program, and the local variable scope is the subroutine that defines the variable.When a global variable has the same name as a local variable:Local variables work in sub-programs

the function can be defined as follows: def calc (numbers): sum = 0 for n in numbers: sum = SUM + N * n * return sum But when called, you need to assemble a list or tuple:>>> calc ([1, 2, 3]) to change the parameter of the function to a variable parameter Def calc (*numbers): sum = 0 for n in numbers: sum = SUM + N * n * ret

# isinstance #查看某个对象是不是某个类的实例# issubclass ## len #查看长度# list ## Memoryview #查看内存地址相关类# next ## iter #创建迭代器# object #所有类的复类# Open ## ord ## POW ## Print ## property ## range ## repr ## Reversed #反转# round ## set #集合# slice ## sorted ## Staticmethod ## str #字符串# Super #面向对象# tuple #元祖# type #类型# VARs #当前模块有哪些变量# Zip #压缩# __import__ #导入模块# delattr ()# getattr ()# setattr ()1.1.5 function return valueTo get the result of the function execution, you can return the result with a return statement.1. Th

PHP/** * Policy mode * Policy mode helps build an object that does not have to contain logic itself, but is able to take advantage of algorithms in other objects as needed * The best practice when you can create an object-based, self-contained algorithm of interchangeable objects is to use the policy mode*/Interfacemath{functionCalc$op 1,$op 2);}classAddImplementsmath{ Public functionCalc$op 1,$op 2) { return $op 1+$op 2; }}classSubImplementsmath{ Public functionCalc$op 1,$op 2) {

(String.valueOf("7/6"), calc.getResult()); } @Test public void testSubstract2() { calc.substract2(2,4,2,3); assertEquals(String.valueOf("1/-6"), calc.getResult()); } @Test public void testMultiply2() { calc.multiply2(2,4,2,3); assertEquals(String.valueOf("1/3"), calc.getResult()); } @Test public void testDivide2() { calc.divide2(2,4,2,3); assertEquals(String.valueOf("3/4"), calc.getResult()); } This part of function c

the defer are determined at the time of the Declaration, and first look at an example (production environment that is estimated to be spit-sprayed to death) func calc(index string, a, b int) int { ret := a + b fmt.Println(index, a, b, ret) return ret}func main() { a := 1 b := 2 defer calc("1", a, calc("10", a, b)) a = 0 defer

In the case of a situation, recursive operations are required, but recursion is very large and there are more than 10,000 occurrences. Do not say 10,000 times recursion, the original test code is Java, not installed JDK and compiled environment, or with Python bar First look at the original Java code: public class Upcount { private long calc (int depth) { if (depth = = 0) return 1; Long cc = calc