#include"stdio.h"
#include"string.h"
#define address "jisuanqi.txt"

char stack[200],out[200];
int k=0,t=0;

void up(int a,int b,char flag)
{
    int q;
    if(flag=='*'){
        q=a*b;
        out[k]=q+'0';  //当q大于9时存入错误,下面除法一样
        k++;
    }
    else{
        q=(a-'0')/(b-'0');
        out[k]=q+'0';
        k++;
    }
}

void result()
{
    int len1=strlen(stack)-1,len2=strlen(out)-1;
    while(len2>0)
    {
        if(stack[len1]=='+')out[len2-1]=(out[len2]-'0')+(out[len2-1]-'0')+'0';
        else out[len2-1]=(out[len2-1]-'0')-(out[len2]-'0')+'0';
        len2-=1;
        stack[len1]=NULL;
        len1--;
    }
    printf("%s",out);
}

void translate(char str[])
{
    stack[0]='1';
    char ch,flag;
    int i=0,l=0,j=0;
    int a,b;

    ch=str[i];

    while(ch!='\0')
    {
        switch(ch){
            case '-':
            case '+':
                for(l;l<strlen(stack);l++)
                    if(stack[l]=='*'||stack[l]=='/')break;
                    flag=stack[l];
                    stack[l]=ch;
                    k=k-2;
                    a=out[k]-'0';b=out[k+1]-'0';
                    out[k]=NULL;

                    up(a,b,flag);
                    break;
            case '*':
            case '/':
                stack[t]=ch;t++;
                break;
            default:
                j=0;
                while(ch>='0'&&ch<='9'){
                    j=j*10+(ch-'0');
                    i++;
                    ch=str[i];
                }
                i--;
                out[k]=j+'0';k++;
                break;
        }
        i++;
        ch=str[i];
    }
}

int main()
{
    FILE *fp;
    char str[200];
    fp=fopen(address,"w");
    printf("please input a string:\n");
    gets(str);
    fputs(str,fp);
    translate(str);
    result();
    fputc('=',fp);
    fputs(out,fp);
    fclose(fp);
}