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#include "aoc.h"
namespace aoc2017 {
int day1(line_view lv) {
int sum{0};
const char* p1 = lv.line;
const char* p2 = p1 + 1;
while (*p2 >= '0' && *p2 <= '9') {
if (*p1 == *p2) {
sum += *p1 - '0';
}
p1++;
p2++;
}
if (*p1 == *lv.line) {
sum += *p1 - '0';
}
return sum;
}
int day1part2(line_view lv) {
int sum{0};
size_t size = lv.length % 2 == 0 ? lv.length : lv.length - 1;
const char* p1 = lv.line;
const char* p = lv.line + size / 2;
while (*p1 >= '0' && *p1 <= '9') {
const char* p2 = p1 < p ? (p + (p1 - lv.line)) : (lv.line + (p1 - p));
if (*p1 == *p2) {
sum += *p1 - '0';
}
p1++;
}
return sum;
}
} // namespace aoc2017
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