编译怪谈

Question

问题1 没有结束输出，应改为：
if(counter==10)
cout<<"Ahah! You know the secret.\n";
if(counter>10)
cout<<"You should be able to do better.\n";
if(counter<10)
cout<<"Either you know the secret or you got lucky!"
<<endl;

Answer 1

问题1 没有结束输出，应改为：
if(counter==10)
  cout<<"Ahah! You know the secret.\n";
if(counter>10)
  cout<<"You should be able to do better.\n";
if(counter<10)
  cout<<"Either you know the secret or you got lucky!\n"cout<<endl;问题2
 result 声明为int 所以输入小数，自动取整，（不是四舍五入）
 输入0.XXX时 result = 0;问题3
 getchar()

Answer 2

问题1：语句cout<<"Either you know the secret or you got lucky!"
            <<endl;
和语句cout<<"Either you know the secret or you got lucky!";
      cout<<endl;有什么不同？
问题2：result即使为0也不应该进入无限循环啊

Answer 3

输入0.1会运行到这个函数
int istream::getint(char * buffer)  // returns length
{
    int base, i;
    int c;
    int fDigit = 0;
    int bindex = 1;    if (x_flags & ios::dec)
        base = 10;
    else if (x_flags & ios::hex)
        base = 16;
    else if (x_flags & ios::oct)
        base = 8;
    else
        base = 0;    if (ipfx(0))
        {
        c=bp->sgetc();
        for (i = 0; i<MAXLONGSIZ-1; buffer[i] = (char)c,c=bp->snextc(),i++)
            {
            if (c==EOF)
                {
                state |= ios::eofbit;
                break;
                }
            if (!i)
                {
                if ((c=='-') || (c=='+'))
                    {
                    bindex++;
                    continue;
                    }
                }
            if ((i==bindex) && (buffer[i-1]=='0'))
                {
                if (((c=='x') || (c=='X')) && ((base==0) || (base==16)))
                    {
                    base = 16;  // simplifies matters
                    fDigit = 0;
                    continue;
                    }
                else if (base==0)
                    {
                    base = 8;
                    }
                }
            // now simply look for a digit and set fDigit if found else break            if (base==16)
                {
                if (!isxdigit(c))
                    break;
                }
            else if ((!isdigit(c)) || ((base==8) && (c>'7')))
                break;            fDigit++;
            }
        if (!fDigit)
            {
                state |= ios::failbit;  // <= 运行到这里时，因为不是数字，会设置错误状态，下次在获取输入时因为存在错误状态，直接跳过了，因此，再次接收输入时，必须清除掉错误状态。
                while (i--)
                    {
                    if(bp->sputbackc(buffer[i])==EOF)
                        {
                        state |= ios::badbit;
                        break;
                        }
                    else
                        state &= ~(ios::eofbit);
                    }
                i=0;
                }
        // buffer contains a valid number or '\0'
        buffer[i] = '\0';
        isfx();
        }
    if (i==MAXLONGSIZ)
        {
        state |= ios::failbit;
        }
    return base;
}