#define _CRT_SECURE_NO_DEPRECATE
#include<stdio.h>
#include<limits.h>
unsigned long long number(int n);
int main(void)
{
int num;
printf("你要计算第几个数? (q to quit):\n");
while (scanf("%d", &num) == 1)
{
if (num < 0)
printf("无效的数字\n");
else
{
printf("第%d 个数是%llu\n", num, number(num));
}
printf(" 输入一个0-100的整数 (q to quit):\n ");
printf("可以表示的最大的数为%llu\n", ULLONG_MAX);
}
return 0;
}
unsigned long long number(int n)
{
unsigned long long x1 = 0, x2 = 1, xn = 0;
if (n < 3)
xn = 1;
else
for (int i = 2; i <= n; ++i)
{
xn = x1 + x2;
x1 = x2;
x2 = xn;
}
return xn;
}
上面的程序计算斐波那契数列的第97项时就已经溢出了,如果要求第100项、第10000项。。。。。该怎么办?