Complete day 3

3.c

@@ -0,0 +1,38 @@
+#include "stdio.h"
+
+int tree_count(char[323][31], int, int);
+
+int main() {
+    char lines[323][31];
+
+    int i = 0;
+    while (scanf("%s", lines[i++]) == 1)
+        ;
+
+    long product = 1;
+    product *= tree_count(lines, 3, 1);
+    printf("Answer 1: %ld\n", product);
+
+    product *= tree_count(lines, 1, 1);
+    product *= tree_count(lines, 5, 1);
+    product *= tree_count(lines, 7, 1);
+    product *= tree_count(lines, 1, 2);
+
+    printf("Answer 2: %ld\n", product);
+}
+
+int tree_count(char lines[323][31], int x_inc, int y_inc) {
+
+    int x = 0, y = 0;
+    int trees = 0;
+
+    while (y < 323) {
+        if (lines[y][x] == '#')
+            trees++;
+
+        y += y_inc; x += x_inc;
+        x %= 31;
+    }
+
+    return trees;
+}

3.input

@@ -0,0 +1,323 @@
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