1 files changed, 39 insertions, 0 deletions

diff --git a/2023/11/11b.c b/2023/11/11b.c
new file mode 100644
index 0000000..edb0fd6
--- /dev/null
+++ b/2023/11/11b.c
@@ -0,0 +1,39 @@
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define N 1000
+
+#define ABS(a) ((a)>0 ? (a) : -(a))
+
+uint8_t dr[N], dc[N];
+int64_t i, j, k, n, p, g[N*N][2];
+
+int main() {
+        char line[N];
+        for (i = 0; fgets(line, N, stdin) != NULL; i++) {
+                for (j = 0; line[j] != '\n'; j++) {
+                        if (line[j] == '#') {
+                                g[n][0] = i;
+                                g[n++][1] = j;
+                                dr[i] = dc[j] = 1;
+                        }
+                }
+        }
+
+        for (k = 1; k < i; k++) dr[k] += dr[k-1];
+        for (k = 1; k < j; k++) dc[k] += dc[k-1];
+
+        for (i = 0; i < n; i++) {
+                g[i][0] += 999999 * (g[i][0] - dr[g[i][0]]);
+                g[i][1] += 999999 * (g[i][1] - dc[g[i][1]]);
+        }
+
+        for (i = 0; i < n; i++)
+                for (j = i+1; j < n; j++)
+                        p += ABS(g[i][0] - g[j][0]) + ABS(g[i][1] - g[j][1]);
+
+        printf("%" PRId64 "\n", p);
+        return 0;
+}