fork download
copy 
  1. // C++ program to implement vieta formula  
  2. // to calculate polynomial coefficients. 
  3. #include <bits/stdc++.h> 
  4. using namespace std; 
  5.  
  6. // Function to calculate polynomial  
  7. // coefficients. 
  8. void vietaFormula(int roots[], int n) 
  9. { 
  10.     // Declare an array for 
  11.     // polynomial coefficient. 
  12.     int coeff[n + 1]; 
  13.  
  14.     // Set all coefficients as zero initially 
  15.     memset(coeff, 0, sizeof(coeff)); 
  16.  
  17.     // Set highest order coefficient as 1 
  18.     coeff[0] = 1; 
  19.  
  20.     for (int i = 0; i < n; i++) { 
  21.     	cout<<i<<":"<<endl;
  22.         for (int j = i+1; j >0; j--) {
  23.  
  24.             coeff[j] +=   roots[i] * coeff[j - 1]; 
  25.             cout<<j<<" "<<coeff[j]<<" "<<roots[i]<<" "<<coeff[j-1]<<endl;
  26.         } 
  27.     } 
  28.  
  29.     cout << "Polynomial Coefficients: "; 
  30.     for (int i = n; i >= 0; i--) { 
  31.         cout << coeff[i] << " "; 
  32.     } 
  33. } 
  34.  
  35. // Driver code 
  36. int main() 
  37. { 
  38.     // Degree of required polynomial 
  39.     int n = 4; 
  40.  
  41.     // Initialise an array by 
  42.     // root of polynomial 
  43.     int roots[] = {-1, 2, -3, 7};
  44.  
  45.     // Function call 
  46.     vietaFormula(roots, n); 
  47.  
  48.     return 0; 
  49. }
Success #stdin #stdout 0.01s 5536KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
0:
1 -1 -1 1
1:
2 -2 2 -1
1 1 2 1
2:
3 6 -3 -2
2 -5 -3 1
1 -2 -3 1
3:
4 42 7 6
3 -29 7 -5
2 -19 7 -2
1 5 7 1
Polynomial Coefficients: 42 -29 -19 5 1
https://ideone.com/sEwu4t
language:
C++14 (gcc 8.3)
created:
1 year ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!