求阶乘

public class Factor{
        public static void main(String arg[]){
                int i=1,j=1,iR=0;
                int[] arr = new int[]{2,4,6,10};
                for(i=0;i<arr.length;i++){
                        iR = doFactor(arr[i]);
                        System.out.println(arr[i] + "的阶乘为：" + iR);
                }
        }
        //求阶乘
        private static int doFactor(int iNum){
                int iR=iNum,j=0;
                for(j=1;j<iNum;j++){
                        iR *= j;
                }
                return iR;
        }
}