#include<stdio.h>
#include<math.h>
#define d0 810
#define half_life 5730
int main(void)
{
int w, d,count=0,age;
double year;
while (scanf("%d%d", &w, &d) && w && d)
{
count++;
year = (log((double)d0 * w /d ) / log(2.0))*half_life; //log()計算以2爲底的自然對數,即log()=ln();
if (year > 10000)
age = 1000 * (int)(year / 1000 + 0.5);
else
age = 100 * (int)(year / 100 + 0.5);
printf("Sample #%d\nThe approximate age is %d years.\n\n", count, age);
}
return 0;
}
注:1.以上C-14半衰期公式引自 http://blog.sina.com.cn/s/blog_69f23b380100o0to.html
2.四捨五入方法引自
http://blog.csdn.net/zxy_snow/article/details/5728636