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#include "aoc.h"
namespace aoc2020 {
int count(char c, const char* p) {
int total{0};
while (*p >= 'a' && *p <= 'z') {
if (*p == c) {
total++;
}
p++;
}
return total;
}
void minmax(int* min, int* max, const char* p1, const char* p2) {
int* p = min;
while (p1 < p2) {
if (*p1 >= '0' && *p1 <= '9') {
*p = *p * 10 + *p1 - '0';
} else {
p = max;
}
p1++;
}
}
// 8-10 g: gggggggggg
bool is_valid1(line_view lv) {
const char* p = lv.contains(":");
int n = count(*(p - 1), p + 2);
int min{0};
int max{0};
minmax(&min, &max, lv.line, p - 2);
return n >= min && n <= max;
}
bool is_valid2(line_view lv) {
const char* p = lv.contains(":");
int p1{0};
int p2{0};
minmax(&p1, &p2, lv.line, p - 2);
bool b1 = *(p + 1 + p1) == *(p - 1);
bool b2 = *(p + 1 + p2) == *(p - 1);
return int(b1) + int(b2) == 1;
}
std::pair<int, int> day2(line_view file) {
int total0{0};
int total1{0};
per_line(file, [&total0, &total1](line_view lv) {
total0 += int(is_valid1(lv));
total1 += int(is_valid2(lv));
return true;
});
return {total0, total1};
}
} // namespace aoc2020
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