C++

Forum

 
Single Link List Problem Deleting Node

Mar 1, 2017 at 9:34am
bird1234 (126)
Node is not deleting

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
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
 
  #include<iostream>
using namespace std;

struct dellist
{
	dellist *next;
	dellist *add;
	dellist *head;
	dellist *last;
	dellist *del1;
	int data;
	void insert(int);
	void display();
	void del(int);
	dellist()
	{
		add = NULL;
		del1 = NULL;
	}
};

void dellist::insert(int item)
{
	if (add == NULL)
	{
		add = new dellist;
		add->next = NULL;
		add->data = item;
		head = add;
		del1 =  add;
		last = add;
	}
	else
	{
		add = new dellist;
		add->next = NULL;
		add->data = item;
		last->next = add;
		last = add;
	}
}

void dellist::display()
{
	if (add == NULL)
	{
		cout << "\nList is Empty\n";
	}
	else
	{
		dellist *temp = head;
		while (temp != NULL)
		{
			cout << temp->data << " , ";
			temp = temp->next;
		}
	}
}

void dellist::del(int del)
{
	dellist *deltemp = head;
	bool check = false;
	if (del1 == NULL)
		cout << "\nList is Empty\n";
	else
	{
		if (del1 == head)
		{
			if (del1->data == del)
			{
				delete del1;
				del1 = del1->next;
				head = del1;
			}
			else
			{
				while (del1 != NULL)
				{
					if (del1->data == del)
					{
						deltemp->next = del1;
						delete del1;
						check = true;
						break;
					}
					else
					{
						deltemp = del1;
						del1 = del1->next;
					}
				}
			}
		}
	}

	if (check == false)
		cout << "\nData Not Found in The List\n";
	else
		cout << "\nData is Seccussfully Deleted\n";



}

int main()
{
	dellist dl;


	int num = 0;
	while (true)
	{
		cout << "\n1-Add Data\n";
		cout << "\n2-Display Data\n";
		cout << "\n3-Delete Data\n";
		cout << "\n4-Quit\n";
		cout << "\nEnter The Choice : ";
		cin >> num;
		if (num == 1)
		{
			cout << "\nEnter The Number : ";
			cin >> num;
			dl.insert(num);
		}
		else if (num == 2)
			dl.display();
		else if (num == 3)
		{
			cout << "\nEnter The Number You Want To Delete : ";
			cin >> num;
			dl.del(num);
		}
		else if (num == 4)
		{
			cout << "\nCome Again\n";
			break;
		}
		else
		{
			cout << "\nWrong Input\n";
		}
		system("pause");
		system("cls");
	}
	system("pause");
}
Edit & run on cpp.sh
Last edited on Mar 1, 2017 at 9:47am
Mar 1, 2017 at 11:17am
bird1234 (126)
anyone
Mar 1, 2017 at 11:51am
MikeyBoy (5631)
Your code could use some comments. It's not immediately clear what the purpose of some of your data members is, e.g. add, del1. The easier you make it for us to understand your code, the more likely people are to take the time and effort to look at it.
Mar 1, 2017 at 12:08pm
coder777 (8449)
I would suggest to do this without add and del1. The more variables are involved the more problems they may cause.

Line 72: del1 is deleted and then used afterward.
Line 83: del1 is deleted but used as next the line above. I would guess you mean deltemp->next = del1->next;
Mar 1, 2017 at 12:21pm
bird1234 (126)
thnx buddy now its working
Last edited on Mar 1, 2017 at 12:21pm
Mar 1, 2017 at 12:28pm
bird1234 (126)
can you explain this deltemp->next = del1->next;
Last edited on Mar 1, 2017 at 12:28pm
Mar 1, 2017 at 2:40pm
coder777 (8449)
can you explain this
This is the way to unlink del1 from a singly linked list. The pointer to del1 will be overwritten with the pointer of the following element (null if there is none). Which effectively removes del1 from the list.
Topic archived. No new replies allowed.