blob: 28c335e32b646e8db49147ba91dc4e6230670061 (
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
|
#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#define INPUT_LEN 1000
#define SEARCH_LEN 25
bool has_sum(uint64_t *cur_num)
{
uint64_t search = *cur_num;
uint64_t *p1 = cur_num - SEARCH_LEN;
do {
uint64_t *p2 = cur_num - SEARCH_LEN;
do {
if (*p1 + *p2 == search) {
return true;
}
} while (++p2 < cur_num);
} while (++p1 < cur_num);
return false;
}
int exe_program(const char *filename)
{
FILE *file = fopen(filename, "r");
// Include space for newline and string terminator
char buffer[24] = { 0 };
uint64_t nums[INPUT_LEN] = { 0 };
size_t num_size = 0;
while (fgets(buffer, 24, file)) {
nums[num_size++] = strtoull(buffer, NULL, 10);
}
fclose(file);
uint64_t *cur_num = nums + SEARCH_LEN;
uint64_t search = -1;
do {
if (!has_sum(cur_num)) {
search = *cur_num;
break;
}
} while (++cur_num < nums + num_size);
cur_num = nums;
do {
uint64_t min = __UINT64_MAX__;
uint64_t max = 0;
uint64_t sum = 0;
uint64_t *p1 = cur_num;
do {
if (*p1 < min) {
min = *p1;
}
else if (*p1 > max) {
max = *p1;
}
sum += *p1;
if (sum == search) {
return min + max;
}
} while (++p1 < nums + num_size);
} while (++cur_num < nums + num_size);
return -1;
}
int main(int argc, char *argv[])
{
printf("%i\n", exe_program(argv[argc - 1]));
}
|
