4-tajriba ishi. Dinamik ma’lumotlar tuzilmasini tadqiq qilish. Chiziqli bog’langan ro’yhatlar

Ishni bajarishga namuna
Topshiriq variantlariga o’xshash bitta misolni yechish dasturini ko’rib chiqamiz. Quyidagicha masala qo’yilgan bo’lsin. Ro’yhatning maksimal elementi topilsin. Ushbu masalaning algoritmi, dasturiy kodi va natijasi quyida keltirilgan.
Algoritm

1. 
   Ekranga menyu chiqaramiz: 1 - element qo’shish; 2 - ro’yhatni ko’rish; 3 - ro’yhat maksimalini topish; 0 - chiqish; tanlash uchun tanla o’zgaruvchisiga qiymat so’raymiz. 2-qadamga o’tish.
   
2. 
   Agar tanla=1 bo’lsa, 3-qadamga, 2 ga teng bo’lsa, 4-qadamga, 3 tanlansa, 6-qadamga o’tish, 0 tanlansa dasturni yakunlash.
   
3. 
   Navbatdagi elementni yaratish p; (p ning info maydoniga qiymat so’rab olib yozish va ptr maydoniga NULL yozish) Agar ro’yhat boshi ko’rsatkichi lst=NULL bo’lsa, lst=p va last=p; aks holda last – ro’yhat oxirgi elementi ptr maydoniga p ni yozib, p elementni last qilib belgilaymiz. 1-qadamga o’tamiz.
   
4. 
   Agar lst NULL ga teng bo’lsa, ro’yhat bo’shligini ekranga chiqarib, 1-qadamga o’tish. Aks holda, p=lst va 5-qadamga o’tish.
   
5. 
   Agar p ning ptr maydoni NULL bo’lmasa, p ning info maydonini ekranga chiqaramiz va keyingi elementga o’tamiz, ya’ni p=p->ptr, 5-qadamga o’tamiz, aks holda, 1-qadamga o’tamiz.
   
6. 
   max=lst->info, ya’ni max o’zgaruvchisiga ro’yhat 1-elementi info maydoni qiymatini o’zlashtiramiz. p=lst va 7-qadamga o’tish.
   

7. 
   Agar p NULL ga teng bo’lmasa, 8-qadamga o’tamiz, aks holda max ni ekranga chiqaramiz va 1-qadamga o’tamiz.
   
8. 
   Agar max< p->info bo’lsa, max=p->info. Keyingi elementga o’tamiz, ya’ni p=p->ptr. 7-qadamga o’tamiz.
   

Dastur kodi
#include
using namespace std;
class Node{
public: int number;
Node* next;
};
int main()
{ Node* head = NULL;
Node* lastPtr = NULL;
short action = -1;
while (1)
{ cout<<"1. element qo’shish\n";
cout<<"2. ro’yhatni ko’rish\n";
cout<<"3. ro’yhat maksimalini topish\n";
cout<<"0. chiqish\n\n";
cout<<"tanlang: ";
cin>>action;
if (action == 0) {
system("CLS");
break;}
if (action == 1)
{ system("CLS");
Node* ptr = new Node;
int numb = -1;

cout<<"son kiriting: ";
cin>>numb;
ptr->number = numb;
ptr->next = NULL;
if (head == 0)
{ head = ptr;
lastPtr = ptr;
system("CLS");
continue;
}
lastPtr->next = ptr;
lastPtr = ptr;
system("CLS");
continue;
}
if (action == 2){
Node* ptr = NULL;
system("CLS");
if (head == 0)
{ cout<<"\t!!! ro’yhat bo’sh !!!\n\n";
system("PAUSE");
system("CLS");
continue;
}
cout<<"* * * * * ro’yhat * * * * *\n\n";
ptr = head;
while (1) {
cout<
number<<" ";
if (ptr->next == 0) break;
ptr = ptr->next;
}
cout<<"\n\n";
system("PAUSE");
system("CLS");
continue;
}
if (action == 3)
{
system("CLS");
Node* p = head;
Node* q = new Node;
Node* last = new Node;
int max=p->number; q=head;
while(p){
if(max
number){ max=p->number;}
p=p->next;
}
system("CLS");
cout<<"max="<
system("pause");
continue;
}
}}