From cf87e5f67ae18767b933edb3b1371696f6b1c582 Mon Sep 17 00:00:00 2001
From: Matthew Sotoudeh <matthewsot@outlook.com>
Date: Fri, 7 Oct 2022 12:46:02 -0700
Subject: algorithms

---
 alg_r.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 alg_r.c

(limited to 'alg_r.c')

diff --git a/alg_r.c b/alg_r.c
new file mode 100644
index 0000000..755fb65
--- /dev/null
+++ b/alg_r.c
@@ -0,0 +1,65 @@
+#include <stdlib.h>
+#include <assert.h>
+#include <stdio.h>
+
+int main(int argv, char **argc) {
+    if (argv < 3) {
+        assert(argv > 0);
+        printf("Usage: %s [n] [t]\n", argc[0]);
+        return -1;
+    }
+
+    size_t n = atoi(argc[1]),
+           t = atoi(argc[2]);
+
+    assert(1 < t && t < n);
+
+    size_t *c = calloc(t + 2, sizeof(*c));
+    size_t j;
+
+R1_initialize:
+    for (size_t j = 1; j <= t; j++)
+        c[j] = j - 1;
+    c[t + 1] = n;
+
+R2_visit:
+    for (size_t k = t; k >= 1; k--)
+        printf("%lu ", c[k]);
+    printf("\n");
+
+R3_maybe_easy_case:
+    if ((t % 2) == 1) {
+        if (c[1] + 1 < c[2]) {
+            c[1] = c[1] + 1;
+            goto R2_visit;
+        }
+        j = 2;
+        goto R4_try_decrease_c_j;
+    } else {
+        if (c[1] > 0) {
+            c[1] = c[1] - 1;
+            goto R2_visit;
+        } else {
+            j = 2;
+            goto R5_try_increase_c_j;
+        }
+    }
+
+R4_try_decrease_c_j:
+    if (c[j] >= j) {
+        c[j] = c[j - 1];
+        c[j - 1] = j - 2;
+        goto R2_visit;
+    }
+    j = j + 1;
+
+R5_try_increase_c_j:
+    if (c[j] + 1 < c[j + 1]) {
+        c[j - 1] = c[j];
+        c[j] = c[j] + 1;
+        goto R2_visit;
+    } else {
+        j = j + 1;
+        if (j <= t) goto R4_try_decrease_c_j;
+    }
+}
-- 
cgit v1.2.3