blob: feeaf686a96e7f42342096f883d50f22fdd14df2 (
plain)
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
|
#include <stdio.h>
#include <stdlib.h>
int *arr;
size_t len = 0;
int
get_parent(int i)
{
return (i - 1) / 2;
}
int
get_left_child(int i)
{
return i * 2 + 1;
}
int
get_right_child(int i)
{
return i * 2 + 2;
}
void
heapify_down(int i)
{
int l = get_left_child(i);
int r = get_right_child(i);
if (i >= len || l >= len) {
return;
}
int left_val = arr[l];
int right_val = arr[r];
int val = arr[i];
if (right_val > left_val && val > left_val) {
arr[i] = left_val;
arr[l] = val;
heapify_down(l);
} else if (left_val > right_val && val > right_val) {
arr[i] = right_val;
arr[r] = val;
heapify_down(r);
}
}
void
heapify_up(int i)
{
if (i == 0) {
return;
}
int p = get_parent(i);
int parent_val = arr[p];
int child_val = arr[i];
if (parent_val > child_val) {
arr[i] = parent_val;
arr[p] = child_val;
heapify_up(p);
}
}
void
insert(int val)
{
arr = realloc(arr, ++len * sizeof(int));
arr[len - 1] = val;
heapify_up(len - 1);
}
int
delete()
{
if (len == 0) {
return -1;
}
int val = arr[0];
if (len == 1) {
free(arr);
return val;
}
arr[0] = arr[--len];
heapify_down(0);
arr = realloc(arr, len * sizeof(int));
return val;
}
int
main()
{
arr = calloc(len, sizeof(int));
insert(5);
insert(3);
insert(9);
insert(7);
for (int i = 0; i < len; ++i) {
printf("%d ", arr[i]);
}
printf("\n");
delete();
for (int i = 0; i < len; ++i) {
printf("%d ", arr[i]);
}
printf("\n");
return 0;
}
|
