栈的建立

#include <stdio.h>
#include<string.h>
#include<stdlib.h>
#include<time.h>
const int maxn = 1e5 + 10;
typedef struct SNode* Stack;
struct SNode {
	int data;
	struct SNode* next;

};
Stack CreatStack() {
	Stack  ptrl;
	ptrl = (Stack)malloc(sizeof(struct SNode));
	ptrl->next = NULL;
	return ptrl;
}
void push(Stack p, int item) {
	Stack  ptrl;
	ptrl = (Stack)malloc(sizeof(struct SNode));
	ptrl->data = item;
	ptrl->next = p->next;
	p->next = ptrl;
}
int pop(Stack p) {
	Stack  ptrl;

	int item;
	if (p->next == NULL) {
		printf("堆栈空");
		return NULL;
	}
	else {
		ptrl = p->next;
		p->next = ptrl->next;
		item = ptrl->data;
		free(ptrl);
		return item;
	}

}
int main() {
	/*freopen("E:/c++/input.txt", "r", stdin);
	freopen("E:/c++/output.txt", "w", stdout);*/
	int n;
	while (scanf("%d", &n),n != -1) {
		Stack stack = CreatStack();
		int s = n;
		while (n > 0) {
			push(stack, n % 2);
			n = n / 2;
		}
		printf("%d--->",s);
		if (s == 0) {
			printf("0"); 
		}
		while (stack->next != NULL) {
			printf("%d", pop(stack));
		}
		printf("\n");

	}
	//fclose(stdin);//关闭重定向输入
	//fclose(stdout);//关闭重定向输出 
	return 0;


}