输入一个正整数n的值,输出1!-2!
+3!-4!+5!……n!的值
n的范围是多少?
供参考:
#include <stdio.h>
int main()
{
int n, i;
double s = 0, jc = 1.0;
scanf("%d", &n);
for (i = 1; i <= n; i++) {
jc *= i;
i % 2 == 0 ? s -= jc : s += jc;
}
printf("%.0f", s);
return 0;
}