-
Notifications
You must be signed in to change notification settings - Fork 0
/
18.4-sum.c
119 lines (109 loc) · 3.36 KB
/
18.4-sum.c
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
/*
* @lc app=leetcode id=18 lang=c
*
* [18] 4Sum
*/
// @lc code=start
/**
* Return an array of arrays of size *returnSize.
* The sizes of the arrays are returned as *returnColumnSizes array.
* Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().
*/
#include <stdlib.h>
int int_cmp(const void *a, const void *b)
{
return (*(int *)a - *(int *)b);
}
int **fourSum(int *nums, int numsSize, int target, int *returnSize, int **returnColumnSizes)
{
int base = 100;
int **ret = (int **)malloc(sizeof(int *) * base);
*returnColumnSizes = (int *)malloc(sizeof(int) * base);
*returnSize = 0;
qsort(nums, numsSize, sizeof(int), int_cmp);
for (int i = 0; i < numsSize; i++)
{
if (i != 0 && nums[i] == nums[i - 1])
{
continue;
}
for (int j = i + 1; j < numsSize; j++)
{
if (j != i + 1 && nums[j] == nums[j - 1])
{
continue;
}
int left = j + 1, right = numsSize - 1;
while (left < right)
{
long sum = (long)nums[i] + nums[j] + nums[left] + nums[right];
if (sum == target)
{
if (*returnSize == base)
{
base *= 1.5;
ret = (int **)malloc(sizeof(int *) * base);
*returnColumnSizes = (int *)malloc(sizeof(int) * base);
}
ret[*returnSize] = (int *)malloc(sizeof(int) * 4);
ret[*returnSize][0] = nums[i];
ret[*returnSize][1] = nums[j];
ret[*returnSize][2] = nums[left];
ret[*returnSize][3] = nums[right];
(*returnColumnSizes)[*returnSize] = 4;
(*returnSize)++;
while (left < right)
{
left++;
if (nums[left] != nums[left - 1])
{
break;
}
}
}
else if (sum < target)
{
while (left < right)
{
left++;
if (nums[left] != nums[left - 1])
{
break;
}
}
}
else
{
while (left < right)
{
right--;
if (nums[right] != nums[right + 1])
{
break;
}
}
}
}
}
}
return ret;
}
// @lc code=end
#include <stdio.h>
int main(int argc, char const *argv[])
{
int nums[] = {1000000000, 1000000000, 1000000000, 1000000000};
int base = 108;
int *returnSize = (int *)malloc(sizeof(int) * base);
int **returnColumnSizes = (int **)malloc(sizeof(int *) * base);
int **ret = fourSum(nums, 4, 0, returnSize, returnColumnSizes);
for (int i = 0; i < *returnSize; i++)
{
printf("\n");
for (int j = 0; j < (*returnColumnSizes)[i]; j++)
{
printf("%d, ", ret[i][j]);
}
}
return 0;
}