实现1！+2！+3！+........+10!总和

[java]代码库

package com.xaygc;
public class fortest {
	public static void main(String args[]){
		int i,j,pat,sum=0;
		for(i=1;i<=20;i++){
			pat=1;
			for(j=1;j<=i;j++){
				pat=pat*j;
			}
			sum=sum+pat;
		}
		System.out.println("1!+2!+3!+....+20!="+sum);
	}
}