2016 day3 part1

1 files changed, 34 insertions, 0 deletions

diff --git a/src/2016/day3/aoc.cpp b/src/2016/day3/aoc.cpp
index 55f4247..bd10b4f 100644
--- a/src/2016/day3/aoc.cpp
+++ b/src/2016/day3/aoc.cpp
@@ -2,4 +2,38 @@
 
 namespace aoc2016 {
 
+void get_number(const char** pp, int* d) {
+  const char* p = *pp;
+  while (*p >= '0' && *p <= '9') {
+    *d = *d * 10 + *p - '0';
+    p++;
+  }
+  *pp = p;
 }
+
+bool is_triangle(line_view lv) {
+  const char* p = lv.line;
+  int is[3] = {0};
+  size_t i{0};
+  while (p < lv.line + lv.length) {
+    if (*p >= '0' && *p <= '9') {
+      get_number(&p, &is[i++]);
+    }
+    p++;
+  }
+  auto b1 = is[0] + is[1] > is[2];
+  auto b2 = is[0] + is[2] > is[1];
+  auto b3 = is[1] + is[2] > is[0];
+  return b1 && b2 && b3;
+}
+
+int day3(line_view file) {
+  int total{0};
+  per_line(file, [&total](line_view lv) {
+    total += int(is_triangle(lv));
+    return true;
+  });
+  return total;
+}
+
+} // namespace aoc2016