Apilar application_calculation de fórmulas de cálculo distribuidas por prioridad del operador (código, análisis, ensamblaje)

Código:

LinkList.h
LinkList.c
LinkStack.h
LinkStack.c
tabla pila lineal

C Principal

#include <stdio.h>
#include "LinkStack.h"

//该程序用栈来计算算式 
/*
 比如：1*5+6/(5-3)  可以转换成 15*653-/+ 字符串进行运算
 注意：每个数只能是一位数
 */
 


int isNumber(char c)//检测是否是数字
{
    
    
    return ('0' <= c) && (c <= '9');
}

int isOperator(char c)//检测是否是加减乘除符号
{
    
    
    return (c == '+') || (c == '-') || (c == '*') || (c == '/');
}

int value(char c)//字符返回数值
{
    
    
    return (c - '0');
}

int express(int left, int right, char op)//计算两个值加减乘除
{
    
    
    int ret = 0;
    
    switch(op)
    {
    
    
        case '+':
            ret = left + right;
            break;
        case '-':
            ret = left - right;
            break;
        case '*':
            ret = left * right;
            break;
        case '/':
            ret = left / right;
            break;
        default:
            break;
    }
    
    return ret;
}

int compute(const char* exp)//将字符串的算式计算结果
{
    
    
    LinkStack* stack = LinkStack_Create();//创建栈
    int ret = 0;
    int i = 0;
    
    while( exp[i] != '\0' )//将每个字符取出
    {
    
    
        if( isNumber(exp[i]) )//如果是数字
        {
    
    
			
            LinkStack_Push(stack, (void*)value(exp[i]));//将数值转成地址进栈 9转成000009
        }
        else if( isOperator(exp[i]) )//如果是运算符号
        {
    
    
            int right = (int)LinkStack_Pop(stack);
            int left = (int)LinkStack_Pop(stack);
            int result = express(left, right, exp[i]);//取出两个数值运算
            
            LinkStack_Push(stack, (void*)result);//再将结果进栈
        }
        else
        {
    
    
            printf("Invalid expression!");
            break;
        }
        
        i++;
    }
    
    if( (LinkStack_Size(stack) == 1) && (exp[i] == '\0') )//如果栈内只有一个元素就是最后的运算后进栈的结果
    {
    
    
        ret = (int)LinkStack_Pop(stack);//出栈获取算式结果
    } 
    else 
    {
    
    
        printf("Invalid expression!");
    }
    
    LinkStack_Destroy(stack);//销毁栈
    
    return ret;
}

int main()
{
    
    
    printf("9 + (3 - 1) * 5 + 8 / 2 = %d\n", compute("931-5*+82/+"));
    
	
	getchar();
    return 0;
}

análisis:

Compilacion: