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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct dir Dir;
#define LOG(s) fprintf(stderr, s"\n");
struct dir {
char name[32];
Dir *parent;
Dir *next_sibling;
Dir *child;
int size;
};
char buf[4096];
Dir root = {0};
int sum = 0;
int totalsize(Dir *dir) {
if (dir == NULL) return 0;
int total = dir->size;
Dir *child = dir->child;
while (child != NULL) {
total += totalsize(child);
child = child->next_sibling;
}
if (total <= 100000) sum += total;
return total;
}
void process_ls(FILE* fp, Dir *cur) {
while (1) {
int c = fgetc(fp);
if (c == EOF) return;
ungetc(c, fp);
if (c == '$') {
return;
}
buf[0] = '\0';
fgets(buf, 4096, fp);
if (buf[0] == 'd') {
strtok(buf, " ");
char *childname = strtok(NULL, "\n");
Dir *newdir = malloc(sizeof(Dir));
strcpy(newdir->name, childname);
newdir->parent = cur;
newdir->next_sibling = cur->child;
newdir->child = NULL;
newdir->size = 0;
cur->child = newdir;
} else {
char *pos;
long fsz = strtol(buf, &pos, 10);
cur->size += fsz;
}
}
}
void process_cmd(FILE *fp, Dir **pcur) {
Dir *cur = *pcur;
char *cmd = strtok(buf + 2, " \n");
if (strcmp(cmd, "cd") == 0) {
char *param = strtok(NULL, " \n");
if (strcmp(param, "/") == 0) {
*pcur = &root;
} else if (strcmp(param, "..") == 0) {
*pcur = cur->parent;
} else {
Dir *t = cur->child;
while (t != NULL) {
if (strcmp(t->name, param) == 0) {
*pcur = t;
break;
} else {
t = t->next_sibling;
}
}
}
} else if (strcmp(cmd, "ls") == 0) {
process_ls(fp, cur);
}
}
int main() {
FILE *fp = fopen("input", "r");
Dir *cur = &root;
while (fgets(buf, 4096, fp)) {
int len = strlen(buf);
if (len <= 1) continue;
char c = buf[0];
if (c == '$') {
process_cmd(fp, &cur);
}
}
totalsize(&root);
printf("%d\n", sum);
}
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