数的三次方根
浮点数在范围足够小时,便可以认为是一个数
模板
void search() {
double x;
cin >> x;
double l = 0,r = x;
while (r - l > 1e-10) { //正数且是精度为6的
double mid = (l + r) / 2;
if (check(mid)) r = mid;
else l = mid;
}
return l;
}
C++ 代码
include [HTML_REMOVED]
using namespace std;
int main()
{
double x;
cin >> x;
double l = 0, r = x;
while(r - l > 1e-10 || r -l < -1e-10){ // 要求精度为6 区分正数和负数的情况
double mid = (r + l) / 2;
if(x >= 0)
{
if(mid * mid * mid >= x) r = mid;
else l = mid;
}
else
{
if(mid * mid * mid <= x) r = mid;
else l = mid;
}
}
printf(“%lf”,l);
}
```