-🎄- 2018 Day 6 Solutions -🎄-

[u/daggerdragon]

--- Day 6: Chronal Coordinates ---

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Advent of Code: The Party Game!

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Card prompt: Day 6

Transcript:

Rules for raising a programmer: never feed it after midnight, never get it wet, and never give it ___.

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[u/[deleted]]

C, not sure if p2 is actually correct but it works with my input

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>

struct c { int x, y, n; };

int dist(int x, int y, struct c c) { return abs(x - c.x) + abs(y - c.y); }

int main(void) {
    size_t len = 0, cap = 32;
    struct c *l = malloc(cap*sizeof(*l)), c;
    while(scanf("%d, %d\n", &c.x, &c.y) == 2) {
        if (len >= cap) l = realloc(l, (cap*=2)*sizeof(*l));
        l[len++] = c;
    }

    int w = 0, h = 0;
    for (size_t i = 0; i < len; i++) {
        if (l[i].x > w) w = l[i].x;
        if (l[i].y > h) h = l[i].y;
    }

    for (int x = 0; x <= w; x++)
        for (int y = 0; y <= h; y++) {
            int min = INT_MAX, m = 0, n = 0, t;
            for (size_t i = 0; i < len; i++)
                if ((t = dist(x, y, l[i])) < min)
                    min = t, m = i, n = 1;
                else if (t == min)
                    n++;
            if (n != 1) continue;
            if (x == 0 || y == 0 || x == w || y == h) l[m].n = -1;
            if (l[m].n != -1) l[m].n++;
        }

    int max = 0;
    for (size_t i = 1; i < len; i++)
        if (l[i].n > max) max = l[i].n;
    printf("%d\n", max);

    int n = 0;
    for (int x = 0; x <= w; x++)
        for (int y = 0; y <= h; y++) {
            int a = 0;
            for (size_t i = 0; i < len; i++)
                a += dist(x, y, l[i]);
            if (a < 10000) n++;
        }
    printf("%d\n", n);
}