1 files changed, 121 insertions, 0 deletions
diff --git a/usr.bin/learn/lib/editor/L44.1g b/usr.bin/learn/lib/editor/L44.1g
new file mode 100644
index 00000000000..b0eb263675f
--- /dev/null
+++ b/usr.bin/learn/lib/editor/L44.1g
@@ -0,0 +1,121 @@
+#print
+Of course, you can also search for lines that
+contain backslashes; again, it's simply a matter
+of doubling the backslash in the search pattern.
+That is,
+   /\\/
+finds the next line with a backslash.
+
+Find the second occurrence of "\n\n" in the file
+"prog.c", and type "answer N", where N is its
+line number.
+#create prog.c
+
+int  nsave  = 0;
+
+selunit()
+{
+  char fnam[20], s[50];
+  static char dobuff[50];
+  char posslev[20][20];
+  int diff[20], i, k, m, n, best, alts, statb[20];
+  FILE *f;
+  char zb[200];
+  static char saved[20];
+
+  while (ask) {
+    printf("What lesson? ");
+    fflush(stdout);
+    gets(dobuff);
+    if (strcmp(dobuff, "bye") == 0)
+      wrapup(0);
+    level = todo = dobuff;
+    sprintf(s, "../L%s", dobuff);
+    if (access(s, 04) == 0)
+      return;
+    printf("no such lesson\n");
+  }
+  alts = 0;
+retry:
+  f=scrin;
+  if (f==NULL) {
+    sprintf(fnam, "../L%s", level);
+    f = fopen(fnam, "r");
+    if (f==NULL) {
+      fprintf(stderr, "No script for lesson %s.\n", level);
+      wrapup(1);
+    }
+    while (fgets(zb, 200, f)) {
+      trim(zb);
+      if (strcmp(zb, "#next")==0)
+        break;
+    }
+  }
+  if (feof(f)) {
+    printf("Congratulations\n\n.You have finished this sequence.\n");
+    fflush(stdout);
+    todo = 0;
+    return;
+  }
+  for(i=0; fgets(s, 50, f); i++) {
+    sscanf(s, "%s %d", &posslev[i], &diff[i]);
+  }
+  best = -1;
+  /* cycle through lessons from random start */
+  /* first try the current place, failing that back up to
+       last place there are untried alternatives (but only one backup) */
+  n = grand()%i;
+  for(k=0; k<i; k++) {
+    m = (n+k)%i;
+    if (already(posslev[m])) continue;
+    if (best<0) best=m;
+    /* real alternatives */
+    alts++;
+    if (abs(diff[m]-speed) < abs(diff[best]-speed))
+      best=m;
+  }
+  if (best < 0 && nsave) {
+    nsave--;
+    strcpy(level, saved);
+    goto retry;
+  }
+  if (best <0) {
+    /* lessons exhausted or missing */
+    printf("Sorry, there are no alternative lessons at this stage.\n");
+    printf("See someone for help.\n\n");
+    fflush(stdout);
+    todo = 0;
+    return;
+  }
+  strcpy (dobuff, posslev[best]);
+  if (alts>1) {
+    nsave=1;
+    strcpy (saved, level);
+  }
+  todo = dobuff;
+  fclose(f);
+}
+
+abs(x)
+{
+  return(x>=0? x: -x);
+}
+
+grand()
+{
+  static int garbage;
+  int a[2], b;
+
+  time(a);
+  b = a[1]+10*garbage++;
+  return(b&077777);
+}
+#copyin
+#user
+#uncopyin
+#match 73
+#bad 43
+The second______ one.
+#log
+#next
+44.1h 10