C 2024 last day part 1

c/2024/25/code_chronicle.c

@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include "../../lib/aoc.h"
+
+int main() {
+  char *line;
+
+  int locks[2000][5];
+  int locks_count = 0;
+  int keys[2000][5];
+  int keys_count = 0;
+
+  int pins[5];
+
+  do {
+    line = aoc_read_line();
+    if (line == NULL) break;
+
+    for (int j = 0; j < 5; j++) {
+      pins[j] = 0;
+    }
+    
+    if (line[0] == '.') {
+      for (int i = 0; i < 6; i++) {
+	line = aoc_read_line();
+	for (int j = 0; j < 5; j++) {
+	  if (pins[j] == 0 && line[j] == '#') pins[j] = 5 - i;
+	}
+      }
+      for (int j = 0; j < 5; j++) {
+	keys[keys_count][j] = pins[j];
+      }
+      keys_count++;
+    } else if(line[0] == '#') {
+      for (int i = 0; i < 6; i++) {
+	line = aoc_read_line();
+	for (int j = 0; j < 5; j++) {
+	  if (line[j] == '#') pins[j] = i + 1;
+	}
+      }
+      for (int j = 0; j < 5; j++) {
+	locks[locks_count][j] = pins[j];
+      }
+      locks_count++;
+    }
+
+    line = aoc_read_line();
+    if (line == NULL) break;
+
+  } while (line != NULL);
+
+  int pairs = 0;
+  for (int i = 0; i < locks_count; i++) {
+    for (int j = 0; j < keys_count; j++) {
+      for (int k = 0; k < 5; k++) {
+	if (locks[i][k] + keys[j][k] >= 6) goto bad;
+      }
+      pairs++;
+    bad:
+    }
+  }
+
+  printf("Part 1: %d", pairs);
+
+  aoc_free();
+  exit(0);
+}