1 files changed, 45 insertions, 0 deletions

diff --git a/2023/05/5a.c b/2023/05/5a.c
new file mode 100644
index 0000000..15d2805
--- /dev/null
+++ b/2023/05/5a.c
@@ -0,0 +1,45 @@
+#include <inttypes.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define N 100
+
+bool isnum(char c) { return c >= '0' && c <= '9'; }
+
+int main() {
+        char *buf, line[N];
+        int64_t i, m, ns, seed[N], next[N], r[3];
+
+        for (ns = 0, buf = fgets(line, N, stdin); *buf; buf++) {
+                if (!isnum(*buf)) continue;
+                next[ns++] = atoll(buf);
+                while (isnum(*buf)) buf++;
+        }
+
+
+        while ((buf = fgets(line, N, stdin)) != NULL) {
+                if (!isnum(*buf)) {
+                        memcpy(seed, next, ns * sizeof(int64_t));
+                        fgets(line, N, stdin); /* Discard description */
+                        continue;
+                }
+
+                for (i = 0; *buf; buf++) {
+                        r[i++] = atoll(buf);
+                        while (isnum(*buf)) buf++;
+                }
+
+                for (i = 0; i < ns; i++)
+                        if (seed[i] >= r[1] && seed[i] < r[1] + r[2])
+                                next[i] = seed[i] + (r[0] - r[1]);
+        }
+
+        m = next[0];
+        for (i = 1; i < ns; i++)
+                m = m > next[i] ? next[i] : m;
+
+        printf("%" PRId64 "\n", m);
+        return 0;
+}