C编程 求1/1!+2/2!+3/3!+...+n/n! 希望来个简单易懂的程序就好

Question

如题所述

Answer 1

#include <stdio.h>

void main()
{
int i,n;
double x=1,y=0;
scanf("%d", &n);
for (i=1; i<=n; i++)
{
x=x*i;
y+=i/x;
}
printf("%lf\n", y);
}

Answer 2

#include <stdio.h>
#include <stdlib.h>
double CalNJieCheng(int n)
{
int nLoop;
double nResult;

nResult = n;
for(nLoop=1;nLoop<=n;nLoop++)nResult = nResult / nLoop;
return nResult;
}

int main()
{
int nLoop,n;
double nTmp,nSum;
nSum = 0;
printf("Input n:");
scanf("%d",&n);

for(nLoop=1;nLoop<=n;nLoop++)
{
nTmp = CalNJieCheng(nLoop) ;
nSum += nTmp;
}
printf("1/1!+2/2!+3/3!+...+n/n!的值(n=%d)为：%e\n",n,nSum);
system("PAUSE");

return 0;
}

Answer 3

#include <stdio.h>

int main()
{
int n;
scanf("%d", &n);
int result=0;
double x=1;
for (int i = 1; i<n; ++i)
{
x/=1;
result+=i*x;
}
printf("\n%f\n", result);
return 0;
}