4月13日打卡

打卡c++趣味练

6.

 

 

#include<bits/stdc++.h> 
using namespace std;

int nuidun(double a, double b, double c, double d){
    double x0, f, fd, x = 1.5;
    do{
     x0 = x;
    f = a * x0 * x0 * x0 + b * x0 * x0 + c * x0 + d;
    fd = 3 * a * x0 * x0 + 2 * b * x0 + c;
    x = x0 - f / fd;
    }while(fabs( x - x0) >= 1e-5);
    return x;
    
}
int main(){
    double a, b, c, d, x = 1.5;
    double r;
    cin >> a >> b >> c >> d;
    r = nuidun(a, b, c, d);
    cout << r;
    return 0;
    
}

今天写的好慢