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#include "aoc.h"
#include <vector>
#include <climits>
namespace aoc2017 {
int get_number(const char** pp) {
const char* p = *pp;
int d{0};
while (*p >= '0' && *p <= '9') {
d = d * 10 + *p - '0';
p++;
}
*pp = p;
return d;
}
int evenly_divisible(int x, int y) {
int max = std::max(x, y);
int min = std::min(x, y);
return max % min == 0 ? max / min : 0;
}
int diffr(size_t i, const std::vector<int>& v) {
if (i == v.size() - 1) {
return 0;
} else {
for (size_t j = i + 1; j < v.size(); j++) {
int d = evenly_divisible(v[i], v[j]);
if (d > 0) {
return d;
}
}
return diffr(i + 1, v);
}
}
int diff(line_view lv, std::vector<int>& v) {
int max{INT_MIN};
int min{INT_MAX};
const char* p = lv.line;
while (p < lv.line + lv.length) {
if (*p >= '0' && *p <= '9') {
int d = get_number(&p);
if (d > max)
max = d;
if (d < min)
min = d;
v.push_back(d);
}
p++;
}
return max - min;
}
std::pair<int, int> day2(line_view file) {
int sum1{0};
int sum2{0};
per_line(file, [&sum1, &sum2](line_view lv) {
std::vector<int> v;
sum1 += diff(lv, v);
sum2 += diffr(0, v);
return true;
});
return {sum1, sum2};
}
} // namespace aoc2017
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