稍微改了下，这样不会无限循环.....

//created by INSANEFORM


public class ComputingFractions
{
    public static void main(String[] args)
    {
        int num1=1;
        int num2=10;
        int num11=num1;
        int den1=1;
        int den2=10;
        int den11=den1;
        while (num11<=num2)
        {
            num11++;

            while (den11<=den2)
            {
                den11++;
                if (((num11/den11)*den11 !=num11)
                    System.out.println(num11 +" is not represented precisely");
            }
        }
  
    }  
}


但是有一点要LZ注意....两个整形相除的结果不是小数，而是整数....小数部分会被舍弃。