T4.2 计算 e=1-1/1+1/2-1/3+1/4（阶乘）......,直到最后一项的绝对值＜1E-4

#include "stdio.h"
int main()
{
	float sum=1;
	int i,t,j;
	float jc;
	jc=1;
	for(i=1;1/jc>1E-4;i++)
	{
		if(i%2==1)   
		  t=-1;
		else
		  t=1;        
		
		
		 
	    
	    jc=1;
	    for(j=1;j<=i;j++)
	      jc=jc*j;     
	    
	    sum=sum+(1/jc)*t;
	}        
	printf("%f",sum);
}