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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#define INPUTLEN 20000
static int* expand(size_t *lenp, const char *mp, size_t maplen) {
size_t len = 0;
for (size_t i = 0; i < maplen; i++) len += mp[i] - '0';
int *disk = malloc(len * sizeof(int));
size_t cursor = 0;
for (size_t i = 0; i + 1 < maplen; i += 2) {
for (int j = 0; j < mp[i] - '0'; j++) disk[cursor++] = i / 2;
for (int j = 0; j < mp[i+1] - '0'; j++) disk[cursor++] = -1;
}
if (maplen % 2 == 1) {
size_t i = maplen - 1;
for (int j = 0; j < mp[i] - '0'; j++) disk[cursor++] = i / 2;
}
*lenp = len;
return disk;
}
static size_t compact(int *disk, size_t len) {
size_t j = len; // one past the last non-empty block
while (j > 0 && disk[j-1] == -1) j--;
for (size_t i = 0; i < j - 1; i++) {
if (disk[i] != -1) continue;
disk[i] = disk[--j];
while (j > 0 && disk[j-1] == -1) j--;
}
return j;
}
static size_t defragment(int *disk, size_t len) {
// TODO
}
static size_t checksum(int *disk, size_t len) {
size_t sum = 0;
for (size_t i = 0; i < len && disk[i] != -1; i++) {
sum += i * disk[i];
}
return sum;
}
static void print_disk(int *disk, size_t len) {
for (size_t i = 0; i < len; i++) {
if (i != 0) putchar(' ');
if (disk[i] == -1) putchar('.');
else printf("%d", disk[i]);
}
putchar('\n');
}
int main(void) {
char *diskmap = malloc(INPUTLEN + 1);
size_t nr = fread(diskmap, 1, INPUTLEN, stdin);
assert(nr <= INPUTLEN);
while (nr > 0 && isspace(diskmap[nr-1])) nr--;
diskmap[nr] = 0;
size_t disklen;
int *disk = expand(&disklen, diskmap, nr);
int *disk2 = malloc(disklen * sizeof(int));
memcpy(disk2, disk, disklen * sizeof(int));
size_t disklen1 = compact(disk, disklen);
printf("%zu\n", checksum(disk, disklen1));
size_t disklen2 = defragment(disk2, disklen);
printf("%zu\n", checksum(disk2, disklen2));
}
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