求助 1-1/2-1/3-1/4 哪里错了,求大神帮助
											#include "stdio.h"void main()
{
int i,n;
double sum=1.0;
printf("input a number :");
scanf("%d",&n);
for(i=1;i<=n;i++)
sum=sum-1/(n+1);
printf("tatal number is %f\n",sum);
}
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	    2014-07-15 16:37
   2014-07-15 16:40
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	    2014-07-15 16:43
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	    2014-07-15 16:52
   2014-07-15 17:00
	    2014-07-15 17:00