Please I need help. I need the tridiagonal algorithm in the C language. I need i

Question

Please I need help. I need the tridiagonal algorithm in the C language. I need it to have the columns inputed through the keyboard. I can't get my code to run. my suboutine is not working properly. the correct results are....

28.8103
-30.8044
-3.8742
9.4136
-0.4181

void thomas(double aa[5], double bb[5], double cc[5], double dd[5], double u[5], int size1)
{
   int imax = size1;
  
   for (int i = 3; i <= imax-1; i++)
   {
       cc[i] = cc[i] - ((cc[i - 1] * bb[i]) / dd[i - 1]);
       dd[i] = dd[i] - ((bb[i]* aa[i - 1]) / dd[i - 1]);

   }

   u[4] = cc[4] / dd[4];

   for (int i = imax - 2; i >= 0; i--)
   {

       u[i] = (cc[i] - (aa[i] * u[i + 1])) / dd[i];

   }

For your second code, implement Thomas' algorithm. This code should function in the same manner as the Gaussian Elimination code, and the algorithm must be in its own subroutine and called from the main program. Use this code to solve the following systems of equations

Explanation / Answer

void TridiagonalSolve(const double *a, const double *b, double *c, double *d, double *x, unsigned int
int i;
//Modify the coefficients.
c[0] = c[0]/b[0]; //Division by zero risk.
d[0] = d[0]/b[0];
double id;
for(i = 1; i != n; i++){
id = 1.0/(b[i] - c[i - 1]*a[i]); //Division by zero risk.
c[i] = c[i]*id; //Last value calculated is redundant.
d[i] = (d[i] - a[i]*d[i - 1])*id;
}
//Now back substitute.
x[n - 1] = d[n - 1];
for(i = n - 2; i != -1; i--)
x[i] = d[i] - c[i]*x[i + 1];
}

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