#include#include#include#define MAX_STACK_SIZE 100 typedef struct TreeNodeType { char data; struct TreeNodeType *left, *right;}TreeNode; typedef TreeNode* element; typedef struct { element stack[MAX_STACK_SIZE]; int top;}StackType; TreeNode n1 = { 'D', NULL, NULL };TreeNode n2 = { 'E', NULL, NULL };TreeNode n3 = { 'B', &n1, &n2 };TreeNode n4 = { 'F', NULL, NULL };TreeNode n5 = { 'C', &n4, NULL }..