数据结构——栈（C语言实现）

#include <stdio.h>
#include <stdlib.h>
#include<string.h>
#include<malloc.h>
// 栈结构的定义
typedef struct _stack {
	int size;   // 栈存储空间的尺寸
	int* base;   // 栈基址
	int* sp;    // 栈顶
} stack;

void init(stack* s, int n) {
	s->base = (int*)malloc(sizeof(int)*n);
	s->size = n;
	s->sp = s->base;
}

void push(stack* s, int val) {
	if(s->sp - s->base == s->size) {
		puts("none");
		exit(1);
	}
	*s->sp++ = val;
}

int pop(stack* s) {
	if(s->sp == s->base) {
		puts("none");
		exit(2);
	}
	return *--s->sp;
}
int peek(stack*s) {
	if(s->sp == s->base) {
		puts("none");
		exit(2);
	}

	return *(s->sp-1);
}

int empty(stack* s) {
	return s->sp == s->base;
}

void clean(stack* s) {
	if(s->base)
		free(s->base);
}

int main(void) {
	stack s;
	int i,n;
	int num;
	char str[30];
	init(&s, 1000);
	while(1) {

		scanf("%s",str);
		if(strcmp(str,"push")==0) {
			scanf("%d",&num);
			push(&s, num);
		} else if(strcmp(str,"top")==0) {
			printf("%d\n", peek(&s));
		} else if(strcmp(str,"pop")==0) {
			printf("%d\n", pop(&s));
		} else if(strcmp(str,"clear")==0) {
			empty(&s);
		} else if(strcmp(str,"exit")==0) {
			clean(&s);

			break;
		}
	}
	return 0;
}

数据结构——栈（C语言实现） - yyf的博客 - CSDN博客 https://blog.csdn.net/qq_18860653/article/details/80388025