栈是仅在表尾进行插入、删除操作的线性表。即栈 S= (a1, a2, a3, ………,an-1, an)
,其中表尾称为栈顶 /top
,表头称为栈底 /base
。
因为只能在表尾进行操作,因而栈的运算规定就是“后进先出”(LIFO)
和线性表相似,栈也有两种存储构造——程序栈与链栈
1. 程序栈的 C 语言实现
#include <stdio.h>
#include <stdlib.h>
typedef struct Stack {
int *data;// 数据域
int size;// 栈长度, 也是栈顶数组下标 -1
int max;// 栈最大容量
} Stack;
// 初始化
Stack *initStack(int max)
{
struct Stack *stack;
stack = (struct Stack *)malloc(sizeof(struct Stack));
stack->size = 0;
stack->max = max;
stack->data = (int*)malloc(sizeof(int)*max);
return stack;
}
// 压栈
void push(Stack *stack, int item)
{if (stack->size >= stack->max)
{printf("stack is full! \n");
}else{stack->data[stack->size++] = item;
}
}
// 出栈
int pop(Stack *stack)
{if (stack->size >= 0)
{return stack->data[--stack->size];
}
}
//test
int main()
{
struct Stack *stack;
stack = initStack(3);
push(stack,1);
push(stack,2);
push(stack,3);
push(stack,4);
printf("stack out:%d \n", pop(stack));
printf("stack out:%d \n", pop(stack));
push(stack,5);
push(stack,6);
push(stack,7);
printf("stack out:%d \n", pop(stack));
printf("stack out:%d \n", pop(stack));
printf("stack out:%d \n", pop(stack));
return 0;
}
测试成果:
Todo:
- [] 链栈的 C 语言实现