比如当你输入  23.55+20.25# 时 #是结束标志  当我定义一个float的栈是  将我转过来的值23.550000传入栈中时  值就变成了23.549999 不知道有谁知道啊！ 核心代码是
ElemType ch,x;
    float y1=0.0f,y2=0.0f,s,r=0.0f,j=1.0f,k=0.0f;
    push(Z,'#');
    printf("输入算式(以#号结束):");
    ch=getchar();
    gettop(Z,x);
    while(ch != '#' || x != '#')
    {
        
       if(panduan(ch))
           switch(youxianji(x,ch))
       {
            case '<':push(Z,ch);
                ch=getchar();
                break;
            case '=':pop(Z,x);
                ch=getchar();
                break;
            case '>':pop(Z,x);
                pop1(S,y2);
                pop1(S,y1);
                push1(S,operate(y1,y2,x));
       }
       else if(ch >='0' && ch <= '9' || ch == '.')
       {
              s=0.0f;
            
            
              while(ch >= '0' && ch <= '9')
              {
                  s=s*10+ch-48.0f;
                  ch=getchar();
              }

           
         
           
          if(ch == '.')
           {
               ch=getchar();
               r=ch-48.0f;
               r=r/10.0f;
                      j=1.0f/10;
                    printf("r=%f \n j=%f \n",r,j);
        
               ch=getchar();
               while(ch >= '0' && ch <= '9' )
               {
                     j=j/10.0f;
                     r=r+(ch-48)*j;

                     printf("r=%f \n j=%f \n",r,j);
                     ch=getchar();
               }
          }
               
               k=s+r;
               printf("数为:%f \n",k);
               push1(S,k);
               pop1(S,k);
               printf("数为1:%f \n",k);
              
           }
       else
       {
           printf("您输入了非法字符！！！");
           exit(1);
       }

        gettop(Z,x);
      

可是我再用23.55+20.25运行的答案是43.800000  我只是把23.550000传给push1();怎么会丢失精度呢！

但是显示的答案是 43.799999     不知为啥？？？

运行图