【大风】matrix：expression题目代码分享

#include <stdio.h>
//大风的丑陋代码 
int numberStack[]={};//初始化stack，第零位代表长度

//使用的数据结构：栈 
//使用的算法：将第一个数字扔进栈，然后接着读取后面的数字。
//如果是加号相连，则把数字扔进栈，如果是乘号相连 ，则pop出栈中的一个数字，并相乘，再扔进栈。

//最后把栈中的数字全部相加得结果
void push (int newElement,int stack[])
{
    //不告诉你
    //Deadline 2017.1.1 ，慢慢想
}
int pop(int stack[])//若栈为空则返回0
{
    //不告诉你
    //Deadline 2017.1.1 ，慢慢想
}

int main()

{
    int number;
    char opeChar;
    scanf("%d",&number);
    push(number % ,numberStack);
    while ( (opeChar = getchar() )!=EOF)
    {
        scanf("%d",&number);
            if (opeChar == '+')
            {
                push(number% ,numberStack);
            }
            if (opeChar =='*')//本次运算符是*
            {
                push( (pop(numberStack)*(number%)) % ,numberStack);   
            }

    }

    while (numberStack[]>)
    {
        push( ( pop(numberStack)+pop(numberStack) )  %,numberStack);
    }
    printf("%d\n",pop(numberStack));
}
           

comments:当然，本题不一定要用栈，只是那时，我做这道题的时候刚好学了下栈的写法，于是就拿来用了。

推荐大家看看伟元的代码。

关于栈（stack）

In computer science, a stack is an abstract data type that serves as a collection of elements, with two principal operations: push, which adds an element to the collection, and pop, which removes the most recently added element that was not yet removed. The order in which elements come off a stack gives rise to its alternative name, LIFO (for last in, first out). Additionally, a peek operation may give access to the top without modifying the stack.

来源：wiki_stack