New program eccparams.

1 files changed, 38 insertions, 0 deletions

diff --git a/eccparams.c b/eccparams.c
new file mode 100644
index 00000000..60829770
--- /dev/null
+++ b/eccparams.c
@@ -0,0 +1,38 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int
+main (int argc, char **argv)
+{
+  unsigned bits;
+  unsigned max;
+  unsigned c;
+  if (argc < 3)
+    {
+    usage:
+      fprintf(stderr, "Usage: %s: exp-bits max-entries\n", argv[0]);
+      return EXIT_FAILURE;
+    }
+  bits = atoi(argv[1]);
+  if (bits < 2)
+    goto usage;
+  max = atoi(argv[2]);
+  if ( max < 2)
+    goto usage;
+
+  for (c = 3; (1<<c) <= max; c++)
+    {
+      unsigned b;
+      for (b = 1;; b++)
+	{
+	  unsigned s = (1<<c) * b;
+	  unsigned k;
+	  if (s > max)
+	    break;
+	  k = (bits + (c*b) - 1) / (c * b);
+	  printf("k = %2u, c = %2u, S = %3u, T = %3u (%3u A + %2u D)\n",
+		 k, c, s, (b+1)*k, b*k, k);
+	}
+    }
+  return 0;
+}