X-Git-Url: https://git.distorted.org.uk/~mdw/anag/blobdiff_plain/650bb9da7cf5b677960c03e0a6a5616d48340845..904ac13a4c7d86c18d031ad3f113659440ab86b8:/trackword.c?ds=sidebyside

diff --git a/trackword.c b/trackword.c
index b2e3074..ce51e2e 100644
--- a/trackword.c
+++ b/trackword.c
@@ -63,22 +63,16 @@ long isqrt(long a)
 {
   long i, q;
 
-  /* --- Initial guess is half the input length --- */
-
-  for (i = q = a; q; q >>= 2)
-    i >>= 1;
-
-  /* --- Do the main series iteration --- */
+  /* Initial guess is half the input length. */
+  for (i = q = a; q; q >>= 2) i >>= 1;
 
+  /* Do the main series iteration. */
   for (;;) {
-    q = i * i - a;
-    if (!q || (q < 0 && -q <= 2 * i))
-      return (i);
-    q /= 2 * i;
-    if (!q)
-      i--;
-    else
-      i -= q;
+    q = i*i - a;
+    if (q > -2*i && q <= 0) return (i);
+    q /= 2*i;
+    if (!q) i--;
+    else i -= q;
   }
 }
 
@@ -98,21 +92,16 @@ static int track(tcell *c, const char *p)
 {
   tcell **cc;
 
-  if (*p++ != c->ch)
-    return (0);
-  if (!*p)
-    return (1);
-  c->f = 1;
+  if (*p++ != c->ch) return (0);
+  if (!*p) return (1);
 
+  c->f = 1;
   for (cc = c->hop; *cc; cc++) {
-    if ((*cc)->f)
-      continue;
-    if (track(*cc, p)) {
-      c->f = 0;
-      return (1);
-    }
+    if ((*cc)->f) continue;
+    if (track(*cc, p)) { c->f = 0; return (1); }
   }
   c->f = 0;
+
   return (0);
 }
 
@@ -123,12 +112,9 @@ static int n_track(node *nn, const char *p, size_t sz)
   node_track *n = (node_track *)nn;
   tcell *c;
 
-  if (!*p)
-    return (1);
-  for (c = n->c; c->ch; c++) {
-    if (track(c, p))
-      return (1);
-  }
+  if (!*p) return (1);
+  for (c = n->c; c->ch; c++)
+    if (track(c, p)) return (1);
   return (0);
 }
 
@@ -143,48 +129,41 @@ node *trackword(const char *const *av)
   size_t sz = strlen(p);
   tcell *c, **cc, **ccc;
 
-  /* --- Work out the dimensions --- */
-
+  /* Work out the dimensions. */
   x = strcspn(p, "/");
   if (!p[x]) {
     x = isqrt(sz);
-    if (x * x != sz)
+    if (x*x != sz)
       die("bad trackword `%s': not square, and no line markers", p);
     y = x;
   }
 
-  if (!x)
-    die("bad trackword `%s': no columns", p);
+  if (!x) die("bad trackword `%s': no columns", p);
 
   y = 0;
   l = p + sz;
   q = p;
   for (;;) {
-    if (*q == '/')
-      q++;
-    if (!*q)
-      break;
+    if (*q == '/') q++;
+    if (!*q) break;
     if (l - q < x)
       die("bad trackword `%s': inconsistent line lengths", p);
     q += x;
     y++;
   }
 
-  if (!y)
-    die("bad trackword `%s': no rows", p);
-
-  /* --- Build the match node --- */
+  if (!y) die("bad trackword `%s': no rows", p);
 
+  /*  Build the match node. */
   n = xmalloc(sizeof(*n));
   n->n.func = n_track;
   n->x = x; n->y = y;
-  n->c = xmalloc((x * y + 1) * sizeof(tcell));
+  n->c = xmalloc((x*y + 1)*sizeof(tcell));
 
   q = p;
   c = n->c;
   for (j = 0; j < y; j++) {
-    if (*q == '/')
-      q++;
+    if (*q == '/') q++;
     for (i = 0; i < x; i++) {
       c->ch = *q++;
       c->f = 0;
@@ -216,20 +195,15 @@ node *trackword(const char *const *av)
   }
   c->ch = 0;
 
-  /* --- Now prune out bogus links --- */
-
+  /* Now prune out bogus links. */
   for (c = n->c; c->ch; c++) {
     ccc = c->hop;
-    for (cc = c->hop; *cc; cc++) {
-      if (isalpha((unsigned char)(*cc)->ch)) {
-	*ccc++ = *cc;
-      }
-    }
+    for (cc = c->hop; *cc; cc++)
+      if (isalpha((unsigned char)(*cc)->ch)) *ccc++ = *cc;
     *ccc++ = 0;
   }
 
-  /* --- Done --- */
-
+  /* Done. */
   return (&n->n);
 }