diff --git a/best.c b/best.c
index d8489f0..d781f42 100644
--- a/best.c
+++ b/best.c
@@ -61,7 +61,7 @@ int check_best(res, nops, node, values, ops)
         nbests=0;
         found=1;
         //return 1;
-    }/* else if (diff == bestdiff && nops == bestops) {
+    } /*else if (diff == bestdiff && nops == bestops) {
 #       ifdef DEBUG_BEST
         printf("NEW BEST SOLUTION (%d):  res=%d diff=%d nops=%d\n", nbests+1, res, diff, nops);
         print_node(node, TREE_TOP, 0, 0);
diff --git a/eval.c b/eval.c
index fe6ca49..0939a60 100644
--- a/eval.c
+++ b/eval.c
@@ -66,34 +66,33 @@ int eval_node(node, depth, pvals, pops, ncalcs)
                     res=val1*val2;
                 break;
             case Sub:
-                if (val1 != val2) {
-                    if (val1 > val2) {
-                        res=val1-val2;
-                    } else {
-#                       ifdef DEBUG_EVAL2
-                        printf("eval: Sub: swapping val1=%d val2=%d\n", val1, val2);
-#                       endif
-                        res=val2-val1;
-                    }
-                    if (res == val2)              /* already found in subtree */
-                        res=-1;
+                if (val1<val2) {
+                    NODE *tmp=node->left;
+#                   ifdef DEBUG_EVAL2
+                    printf("eval: Sub: swapping val1=%d val2=%d\n", val1, val2);
+#                   endif
+                    node->left=node->right;
+                    node->right=tmp;
                 }
+                if (val1 != val2) {
+                    res=val1-val2;
+                }
+                if (res == val2)                  /* already found in subtree */
+                    res=-1;
                 break;
             case Div:
-                if (val1 >= val2) {
-                    if (val2 != 1 && (val1 % val2 == 0))
-                        res=val1/val2;
-                    if (res == val2)              /* already found in subtree */
-                        res=-1;
-                } else {
+                if (val1<val2) {
+                    NODE *tmp=node->left;
 #                   ifdef DEBUG_EVAL2
-                    printf("eval: Div: swapping val1=%d val2=%d\n", val1, val2);
+                    printf("eval: Sub: swapping val1=%d val2=%d\n", val1, val2);
 #                   endif
-                    if (val1 != 1 && (val2 % val1 == 0))
-                        res=val2/val1;
-                    if (res == val1)              /* already found in subtree */
-                        res=-1;
+                    node->left=node->right;
+                    node->right=tmp;
                 }
+                if (val2 != 1 && (val1 % val2 == 0))
+                    res=val1/val2;
+                if (res == val2)                  /* already found in subtree */
+                    res=-1;
                 break;
             case Nop:
             case End:
diff --git a/lceb.c b/lceb.c
index f8027d6..60993ae 100644
--- a/lceb.c
+++ b/lceb.c
@@ -36,14 +36,14 @@ void help()
     fprintf(stderr, "  -d TYPE: Solutions display type. TYPE can be:\n");
     fprintf(stderr, "           r: RPN (default)\n");
     fprintf(stderr, "           p: Polish\n");
-    fprintf(stderr, "           l: Lisp\n");
+    fprintf(stderr, "           l: Lisp (binary operators)\n");
     fprintf(stderr, "           i: Infix (full parentheses)\n");
     fprintf(stderr, "           d: Suitable for dc(1) input\n");
     fprintf(stderr, "           t: Tree\n");
     fprintf(stderr, "  -i: Show intermediate solutions\n");
     fprintf(stderr, "  -s: Do not show summary (time, nodes evaluated)\n");
     fprintf(stderr, "  -t: Use less trees (Wedderburn–Etherington instead of Catalan)\n");
-    fprintf(stderr, "  -h: this help:\n");
+    fprintf(stderr, "  -h: This help\n");
 }
 
 int main(ac, av)
diff --git a/tree.c b/tree.c
index 27aafdd..6339409 100644
--- a/tree.c
+++ b/tree.c
@@ -66,19 +66,19 @@ void print_node(node, side, depth, details)
         return;
 
     switch (details) {
-        case 1:
+        case 1:                                   /* prefix */
             if (node->type==TREE_NODE) {
                 printf("%c ", node->op);
             } else {
                 printf("%d ", node->val);
             }
-            print_node(node->left, TREE_LEFT, depth+1, details);
             print_node(node->right, TREE_RIGHT, depth+1, details);
+            print_node(node->left, TREE_LEFT, depth+1, details);
             break;
-        case 0:
-        case 5:
-            print_node(node->left, TREE_LEFT, depth+1, details);
+        case 0:                                   /* postfix */
+        case 5:                                   /* dc suitable */
             print_node(node->right, TREE_RIGHT, depth+1, details);
+            print_node(node->left, TREE_LEFT, depth+1, details);
             if (node->type==TREE_NODE) {
                 printf("%c ", node->op);
             } else {
@@ -87,7 +87,7 @@ void print_node(node, side, depth, details)
             if (details==5 && depth==0)
                 printf("p");
             break;
-        case 3:
+        case 3:                                   /* lisp */
             if (node->type==TREE_NODE) {
                 if (!depth) {
                     printf("(%c", node->op);
@@ -105,17 +105,17 @@ void print_node(node, side, depth, details)
                 printf(")");
             }
             break;
-        case 4:
+        case 4:                                   /* infix */
             if (node->type==TREE_NODE) {
                 printf("(");
             }
-            print_node(node->left, TREE_LEFT, depth+1, details);
+            print_node(node->right, TREE_RIGHT, depth+1, details);
             if (node->type==TREE_NODE) {
                 printf(" %c ", node->op);
             } else {
                 printf("%d", node->val);
             }
-            print_node(node->right, TREE_RIGHT, depth+1, details);
+            print_node(node->left, TREE_LEFT, depth+1, details);
             if (node->type==TREE_NODE) {
                 printf(")");
             }