树的直径

The diameter of a tree (sometimes called the width) is the number of nodes on the longest path between two leaves in the tree.

The diameter of a tree T is the largest of the following quantities:

• the diameter of T 's left subtree
• the diameter of T 's right subtree
• the longest path between leaves that goes through the root of T (this can be computed from the heights of the subtrees of T )
• ///直径 #define max(a,b) (a)>(b)?(a):(b) typedef struct Tree { Tree *left; Tree *right; int data; } Tree; int height(Tree *t) { if (t == NULL) { return 0; } else { return 1 + max(height(t->left),height(t->right)); } } int diameter(Tree *t) { if (t == NULL) return 0; int lheight = height(t->left); int rheight = height(t->right); int ldiameter = diameter(t->left); int rdiameter = diameter(t->right); return max(lheight + rheight + 1, max(ldiameter, rdiameter)); }