python programming third edition

its elements can be accessed efficiently and randomly, and the disadvantage is that the performance of inserting and removing elements at a specified location is slow. LinkedList is slower in random access, but it is more efficient to insert and remove elements at a specified location. 2. Set has three important implementations, respectively, Hashset,treeset,linkedhashset all implementation classes of the set interface ensure that their elements are not duplicat

incoming function correspond to which parameters are not obvious. In Objective-c, each value will be paired with the corresponding tag, with the following code:[Partyinstance Addattendee:someperson Withdish:deviledeggs];Remember here that each set of square brackets corresponds to only one message that needs to be sent. Although the addattendee:withdish here: there are two tags, but still only a message, sending this message will only trigger a method.-------------------------------------------

1.script element Properties (6): ①async (Asynchronous script), valid only for external scripts②defer (deferred script), valid only for external scripts③CHARSET,SRC (cross-domain), type,language2. Use external JS files whenever possible, because the browser caches all external JS files according to the settings. That is, if you have 2 pages that use the same file, you only need to download the file once3.①js scripts are generally placed in front of The ②async property, which represents the curren

1. I am a year earlier than JSThe 2.web browser is one of the hosting environments implemented by the ECMAScript.Other hosting environments that implement ECMAScript include node and Adobe Flash3.ECMAScript Main Provisions JS components: syntax, keywords and reserved words;variables, data types, operators, statements, types, objects;4.dom maps the entire page into a multi-node structure. Dom independent of PlatformJavaScript Advanced Programming (3rd

Import java.util.*;public class Exercise13_04 {public static void Main (string[] args) {Scanner input = new Scanner (system.in);System.out.println ("Enter month and Year:");Printcalendar Y = new Printcalendar (Input.nextint (), Input.nextint ());Y.printmonthtitle (); Y.printmonthbody ();}}Class Printcalendar {Calendar value;Public Printcalendar (int Month, int.) {value = new GregorianCalendar (year, Month, 1); }public void Printmonthtitle () {System.out.println ("" + Getmonthname (Value.get (cal

#include /*Rewrite Squeeze (s1,s2) to string S1 any characters in the string S2The matching characters are deleted.*/#define MAX 10Char C[max];int main () {Char A[max] = "ABCDEFG";Char B[max] = "Abcdffe";void Squeeze (char A[],char b[]);Squeeze (A, b);printf ("%s\n", c);}void squeeze (char a[], char b[]) {int i,j;int k=0;int count;for (i=0;icount=0; is importantfor (j=0;jif (a[i]! = B[j]) {//If the characters in a[i] are not equal to any of the characters in B[0]-b[9] count value plus 1count++;}

() {Return age + Run ();}};}();The above example of a direct return object can also be written like this:var box = function () {var age = 100;Function Run () {Return ' running ... ';}var obj = {// Create literal objectGo:function () {Return age + Run ();}};Return obj; return This object}();The literal object declaration, in fact, can be regarded as a singleton pattern in the design pattern, so-called singleton mode, which is always an instance of preserving the Object.Enhanced module mode, whic

Protocol: Implement Mutablecopywithzone: Method, return variable copy Create a new score in the fraction class @interface fraction : nsobject nscopying ; -(id ) Copywithzone: ( Nszone *) zone{fraction *newfact = [[Fraction allocwithzone:zone] init]; [Newfact Setto:numerator Over:denominator]; return newfact;} Fraction *f1 = [[Fraction alloc]init];Fraction *f2;[f1 setTo: 2 over 5copy//产生f1的副本，产生新的Fraction，将f1复制其中[f2 setTo: 1 over: 3print// 2/5 复制的操作对f1没有影响print// 1/3Note :

1.There ' s a fundamental difference between your own code and libraries ofOther people:you can change or extend your own code as you wish, but ifYou want to use someone else's libraries, you usually has to take them asThey is.You can change or expand your own code, but the code for others can only be accepted as it is.2.A number of constructs has sprung up and programming languages toAlleviate this problem. Ruby has modules, and Smalltalk lets packag

Length Number of elements Map (s = + s + "Y") Return a list resulting from adding a "Y" to each of the string element in the list Mkstring (",") Makes a string with the elements of the list Remove (s = s.length==4) Return a list containning al elements of the list except those that has length 4 Reverse Returns a list in reverse order Sort Return a list in alpabetical order

for the left-to-right (I! = 1 and I! = N), you can get the formula:G (i) = f (i-1) + f (n-i)To verify authenticity, verify by n=3.N=3F (1) = 1;F (2) = 3;F (3) = f (1) + F (2) + 1 = 5There are two boundaries and an intermediate point, and the middle point evaluates toG (2) = f (1) + f (1) = 2Then the final result is 2 + 5 * 2 = 12Then 12 times 2 of three squares: 12 * 8 = 96Problem solving.The implementation code is as follows:#include #define MOD (i) (i)% 1000000007Long Longborder[1010] = {0};i

virtual number-(void) print; // print the result-(double) Real;-(double) imaginary; @ end // -------------- implementation section ---------------- @ implementation Complex {double real; double imaginary;}-(void) setreal: (double) A {real = A;}-(void) setimaginary: (double) B {imaginary = B;}-(void) print {nslog (@ "the complex is %. F + %. fi ", real, imaginary);}-(double) Real {return real;}-(double) imaginary {return imaginary ;} @ end // ---------------- program section ------------- int ma