Data Structures and Algorithms(2)

Transcription

1 Mg Zhag Data Structures ad Algorthms Data Structures ad Algorthms(2) Istructor: Mg Zhag Textbook Authors: Mg Zhag, Tegjao Wag ad Haya Zhao Hgher Educato Press, (the "Eleveth Fve-Year" atoal plag textbook)

2 Lear Lst 2. Lear Lst 2.2 Sequetal Lst 2.3 Lked Lst Chapter II Lear Lst a 0 a a 2 a Comparso betwee sequetal lst ad lked lst 2 Mg Zhag Data Structures ad Algorthms

3 Lear 目录页 Lst 2.2 Sequetal Lst 2.2 Sequetal Lst Also kow as the vector, fxed-legth oedmesoal array s used as the storage structure Key Features - Elemets are of the same type - Elemets are sequetally stored cotguous storage space, ad each elemet has a uque dex value - The type of vector legth s costat Implemeted as Array Its elemets are easy to read ad wrte, you ca specfy the locato by usg ts subscrpt - Oce the startg posto s got, all the data elemets of the lst ca be radom accessed 3 Zhag Mg Data Structures ad Algorthms

4 Lear 目录页 Lst 2.2 Sequetal Lst 2.2 Sequetal Lst The formula to calculate the elemets of locato s show as below: 元素地址计算如下所示 : Loc k = Loc k 0 + c, c = szeof(elem) Logcal Address (Subscrpt) Data elemets Store Address Data elemets 0 k 0 Loc(k 0 ) k 0 k Loc(k 0 )+c k k Loc(k 0 )+*c k - k - Loc(k 0 )+(-)*c k - 4 Zhag Mg Data Structures ad Algorthms

5 Lear 目录页 Lst Lear Lst Sequece Lst s Class Defto class arrlst : publc Lst<T> { // sequetal lst,vector prvate: // value types ad value space of lear lst T * alst ; // prvate varables,stace of storage for sequetal lst t maxsze; // prvate varables,maxmum legth of the sequetal lst t curle; // prvate varables,curret legth of the sequetal lst t posto; // prvate varables,curret operato locato publc: arrlst(cost t sze) { // costruct a ew lst,set ts legth to the maxmum maxsze = sze; alst = ew T[maxSze]; curle = posto = 0; ~arrlst() { // destructor fucto used to elmate the stace delete [] alst; 5 Zhag Mg Data Structures ad Algorthms

6 目录页 Lear Lst 2.2 Sequetal Lst Sequece Lst s Class Defto ; vod clear() { // delete the cotet,becomg a empty lst delete [] alst; curle = posto = 0; alst = ew T[maxSze]; t legth(); // returs the curret legth bool apped(cost T value); // apped elemet v at ed bool sert(cost t p, cost T value); // sert a elemet at P bool delete(cost t p); // delete the elemet at P bool setvalue(cost t p, cost T value); // set the value of a elemet bool getvalue(cost t p, T& value); // retur the value of a elemet bool getpos(t &p, cost T value); // seek for a elemet 6 Zhag Mg Data Structures ad Algorthms

7 Lear Lst 目录页 2.2 Sequetal Lst Operatos Sequetal Lst Key dscussos Isert elemet operato bool sert(cost t p, cost T value); Delete elemet operato bool delete(cost t p); Others (Thk by yourselves) 7 Zhag Mg Data Structures ad Algorthms

8 目录页 Lear Lst 2.2 Sequetal Lst Dagram for the serto of sequetal lst k 0 k 0 k k X curr k 2 k 3 X curr k 2 k 3 k 4 k 4 k 5 k 5 8 Zhag Mg Data Structures ad Algorthms

9 Lear Lst 目录页 2.2 Sequetal Lst Iserto of sequetal lst // set the elemet type as T, alst s the array to store Sequetal lst, // maxsze s ts maxmum legth; // p s the sert locato of the ew elemet,retur true f succeeds, // otherwse retur false template <class T> bool arrlst<t> :: sert (cost t p, cost T value) { t ; f (curle >= maxsze) { // check f the SL s overflow cout << "The lst s overflow"<< edl; retur false; f (p < 0 p > curle) { // check f the posto to sert s vald cout << "Iserto pot s llegal"<< edl; retur false; for ( = curle; > p; --) alst[] = alst[-]; // move rght from the ed curle - of the lst utl p alst[p] = value; // sert a ew elemet at p curle++; // adds the curret legth of the lst by retur true; 9 Zhag Mg Data Structures ad Algorthms

10 Lear 目录页 Lst 2.2 Sequetal Lst Dagram for sequetal lst s delete operato 2.2 Sequetal Lst k 0 k 0 k k curr k 2 k 3 curr k 2 k 3 k 4 k 5 k 4 k 5 k 6 k 6 0 Zhag Mg Data Structures ad Algorthms

11 Lear Lst 目录页 2.2 Sequetal Lst Delete operato sequetal lst // set the type of the elemet as T;aLs s the array to store sequetal lst // ad p s the posto of elemets to delete // returs true whe delete succeed,otherwse returs false template <class T> // the type of the elemets of SL s T bool arrlst<t> :: delete(cost t p) { t ; f (curle <= 0 ) { // Check f the SL s empty cout << " No elemet to delete \"<< edl; retur false ; f (p < 0 p > curle-) { cout << "deleto s llegal\"<< edl; retur false ; for ( = p; < curle-; ++) alst[] = alst[+]; // Check f the posto s vald // [p, currle) every elemet move left curle--; // the curret legth of the lst decreases by retur true; Zhag Mg Data Structures ad Algorthms

12 Lear 目录页 Lst Algorthm aalyss of sert ad delete operatos sequetal lst The movemet of elemets the lst Isert: move Delete: move 2.2 Sequetal Lst The probablty values to sert or delete posto are respectvely p ad p The average move tme for sert operato s M = =0 p The average move tme of delete operato s M d = =0 p 2 张铭 数据结构与算法

13 3 目录页张铭 数据结构与算法 Algorthm Aalyss If the probablty to sert or delete every locato SL s the same, amely p = +, p = 2.2 Sequetal Lst Lear Lst Chapter II 2 ) 2( ) ( ) ( ) ( ) ( M 2 2 ) ( ) ( ) ( M d Tme cost s O()

14 Lear 目录页 Lst 2.2 Sequetal Lst Thkg What should you thk about whe dog sert or delete operatos sequetal lst? What advatages ad dsadvatages does sequetal lst have? 4 Zhag Mg Data Structures ad Algorthms

15 Mg Zhag Data Structures ad Algorthms Data Structures ad Algorthms Thaks the Natoal Elaborate Course (Oly avalable for IPs Cha) Mg Zhag, Tegjao Wag ad Haya Zhao Hgher Educato Press, (awarded as the "Eleveth Fve-Year" atoal plag textbook)