后缀式求值

示例输入(基本操作数都是一位正整数!)

59*684/-3*+#

示例输出

57

#include<stdio.h>
#include<stdlib.h>

struct node
{
    int data;
    struct node *next;
};

int main()
{
    struct node *top,*p;
    int x,y;
    char c;
    top=NULL;
    while((c=getchar())!='#')
    {
        if(c>='0'&&c<='9')
        {
            p=(struct node*)malloc(sizeof(node));
            p->data=c-'0';
            p->next=top;
            top=p;
        }
        else if(c=='+'||c=='-'||c=='*'||c=='/')
        {
            y=top->data;
            top=top->next;
            x=top->data;
            if(c=='+')top->data=x+y;
            else if(c=='-')top->data=x-y;
            else if(c=='*')top->data=x*y;
            else if(c=='/')top->data=x/y;
        }
    }printf("%d\n",top->data);
    return 0;
}