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#pragma once
#include "common.h"
#include <vector>
namespace aoc2017 {
struct particle {
int64_t p[3] = {0};
int64_t v[3] = {0};
int64_t a[3] = {0};
int id;
int64_t mdistance() const noexcept { return std::abs(p[0]) + std::abs(p[1]) + std::abs(p[2]); }
friend bool operator<(particle p1, particle p2) { return p1.mdistance() < p2.mdistance(); }
friend bool operator==(particle p1, particle p2) {
return p1.p[0] == p2.p[0] && p1.p[1] == p2.p[1] && p1.p[2] == p2.p[2];
}
// Increase the X velocity by the X acceleration.
// Increase the Y velocity by the Y acceleration.
// Increase the Z velocity by the Z acceleration.
// Increase the X position by the X velocity.
// Increase the Y position by the Y velocity.
// Increase the Z position by the Z velocity.
void tick() {
for (int i = 0; i < 3; i++) {
v[i] += a[i];
p[i] += v[i];
}
}
void get_number(const char** pp, int64_t* d) {
const char* p = *pp;
int sign = 1;
if (*p == '-') {
sign = -1;
p += 1;
}
while (*p >= '0' && *p <= '9') {
*d = *d * 10 + *p - '0';
p++;
}
*d *= sign;
*pp = p;
}
void print() const noexcept {
const int64_t* d[] = {p, v, a};
printf("%d: ", id);
for (int i = 0; i < 3; i++) {
printf("%ld %ld %ld ", *d[i], *(d[i] + 1), *(d[i] + 2));
}
printf("\n");
}
particle(int x, line_view lv) : id(x) {
int64_t* ds[9] = {p, p + 1, p + 2, v, v + 1, v + 2, a, a + 1, a + 2};
int i{0};
const char* p = lv.line;
while (p < lv.line + lv.length) {
if (*p == '-' || (*p >= '0' && *p <= '9')) {
get_number(&p, ds[i++]);
}
p++;
}
}
};
std::pair<int64_t, int64_t> day20(line_view);
} // namespace aoc2017
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