From 3b468ed257608d13345a6a7c7a449216f374c4b8 Mon Sep 17 00:00:00 2001 From: June McEnroe Date: Thu, 10 Dec 2020 00:14:43 -0500 Subject: Solve day 10 part 1 Trivial?? --- 2020/day10.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 2020/day10.c (limited to '2020/day10.c') diff --git a/2020/day10.c b/2020/day10.c new file mode 100644 index 0000000..789f2b1 --- /dev/null +++ b/2020/day10.c @@ -0,0 +1,24 @@ +#include +#include +static int compar(const void *_a, const void *_b) { + const int *a = _a; + const int *b = _b; + return *a - *b; +} +int main(void) { + int list[256]; + int len = 0; + while (EOF != scanf("%d\n", &list[len])) { + len++; + } + list[len++] = 0; + qsort(list, len, sizeof(int), compar); + list[len] = list[len-1] + 3; + len++; + int j1 = 0, j3 = 0; + for (int i = 1; i < len; ++i) { + if (list[i] - list[i-1] == 1) j1++; + if (list[i] - list[i-1] == 3) j3++; + } + printf("%d\n", j1 * j3); +} -- cgit 1.4.1