5好用了

ex5/list.cpp

@@ -43,7 +43,7 @@ Node List::succInsert(Node Old, int New)
     T->pred = Old;
     T->succ = Old->succ;
     Old->succ = T;
-    T->pred->succ = T;
+    T->succ->pred = T;
     _size++;
     return T;
 }
@@ -85,7 +85,7 @@ Node List::succInsertN(Node Old, Node New)
     T->pred = Old;
     T->succ = Old->succ;
     Old->succ = T;
-    T->pred->succ = T;
+    T->succ->pred = T;
     _size++;
     return T;
 }
@@ -144,25 +144,26 @@ void List::removeN(Node i)
     _size--;
 }
 
+Node List::searchN(int value, int n, Node p)
+{
+    while (0 <= n--)
+        if (((p = p->pred)->data) <= value)
+            break;
+    return p;
+}
+
 void List::sort()
 {
-    int sorted = 0;
-    Node p;
-    for (int i = 0; i <= _size - 1 - sorted; i++)
-        for (int j = i; j <= _size - 1 - sorted; j++)
-        {
-            int max = 0;
-            Node maxN;
-
-            p = find(j);
-            if (max < p->data)
-            {
-                max = p->data;
-                maxN = p;
-            }
-
-            maxN->data = p->data;
-            p->data = max;
-            sorted++;
-        }
+    Node p=first();
+    for (int r = 0; r < _size; r++)
+    {
+        succInsert(searchN(p->data,r,p),p->data);
+        p=p->succ;
+        removeN(p->pred);
+    }
+}
+
+int List::valid(Node p)
+{
+    return p && (trailer != p) && (header != p);
 }

ex5/list.h

@@ -17,6 +17,12 @@ private:
     int _size;
 
 protected:
+    Node firstInsertN(Node New);
+    Node lastInsertN(Node New);
+    Node succInsertN(Node old, Node ne);
+    Node predInsertN(Node old, Node ne);
+    void removeN(Node i);
+    Node searchN(int value,int n,Node p);
 
 public:
     int getSize()
@@ -32,14 +38,13 @@ public:
     void lastInsert(int New);
     Node succInsert(Node Old, int New);
     Node predInsert(Node Old, int New);
-    Node firstInsertN(Node New);
-    Node lastInsertN(Node New);
-    Node succInsertN(Node old, Node ne);
-    Node predInsertN(Node old, Node ne);
+
     int get(int i);
     Node find(int i);
     int remove(int i);
-    void removeN(Node i);
+    Node searchN(int value,int n);
+    int valid(Node p);
+    
 
     void sort();