include [HTML_REMOVED]
using namespace std;
/求一个数的三次方根/
/牛顿迭代法*/
int main()
{
double num;
cin>>num;
double x = num;
for(int i=0;i<200;i++)
{
x = (2*x*x*x + num)/(x*x*2);
}
printf("%.6f",x);
return 0;
}
include [HTML_REMOVED]
include [HTML_REMOVED]
using namespace std;
/库函数/
int main()
{
double x;
cin>>x;
printf(“%.6f”,cbrt(x));
return 0;
}
include [HTML_REMOVED]
using namespace std;
/二分法/
int main()
{
double x;
cin>>x;
double l = -10000,r = 10000;
while(r-l>1e-8)
{
double mid = (l+r)/2;
if(midmidmid>=x) r = mid;
else l = mid;
}
printf(“%f”,r);
return 0;
}