解法：

c语言

#include<iostream>
#include<vector>
using namespace std;
typedef struct tNodes{
	char val;
	tNodes* left, * right;
}* tNode;

void creat(tNode& t) {
	char ch;
	cin >> ch;
	if (ch == '#') t= NULL;
	else {
		t = new tNodes;
		t->val = ch;
		creat(t->left);
		creat(t->right);
	}
}
void dfs(tNode& t,char x) {
	if (t == NULL) return;
	if (t->val == x){
		int cnt = 0;
		if (t->left) cnt++;
		if (t->right) cnt++;
		cout << cnt;
		return;
	}
	dfs(t->left, x);
	dfs(t->right, x);
}
int main(){
	tNode root;
	creat(root);
	char x;
	cin >> x;
	dfs(root, x);
	return 0;
}

c++

#include<iostream>
using namespace std;
struct treeNode {
	char val;
	treeNode* left;
	treeNode* right;
	treeNode(char x) :val(x), left(NULL), right(NULL) {};
};
treeNode* buildtree() {
	char ch;
	cin >> ch;
	if (ch == '#') return NULL;
	treeNode* root = new treeNode(ch);
	root->left = buildtree();
	root->right = buildtree();
	return root;
}
void dfs(treeNode* root, char x) {
	if (root == NULL) return;
	if (root->val == x) {
		int cnt = 0;
		if (root->left) cnt++;
		if (root->right) cnt++;
		cout << cnt;
		return;
	}
	dfs(root->left, x);
	dfs(root->right, x);
}
int main() {
	treeNode* root = buildtree();
	char x;
	cin >> x;
	dfs(root, x);
	return 0;
}