public class sum {
		int sum = 0;
		int fum = 1;
		int n;
		public sum(int m)
		{
			n = m;
		}
        public void Countsum()
        { //求和
        	for(int i = 1;i <= n; ++ i)
        	{
                sum += i;
            }
        }
        public void Countfum()
        {//求阶乘
        	for(int i = 1;i <= n;++i)
        	{
                fum *= i;
            }
        }
        public static void main(String []args)
        {
        	sum s=new sum(5);
        	s.Countsum();
        	s.Countfum();
        	System.out.println("1 + 2 + 3 +...+" + s.n + "= " + s.sum);
        	System.out.println(s.n+"!=" + s.fum);
         }
}