二分法求三次方根

 #include<iostream>

using namespace std;

int main(){

double n;

cin>>n;

int l=1,r=n;

while(l+1e-7<r){

double mid=(l+r)/2;

if(mid*mid*mid>=n){

r=mid;
}else

l=mid;

}

printf("%0.6lf",l);

}