#include "umfpack.h"
#include <stdio.h>

void example1()
{
  int n = 5;
  int Ap[] = { 0, 2, 5, 9, 10, 12 };
  int Ai[] = { 0, 1, 0, 2, 4, 1, 2, 3, 4, 2, 1, 4 };
  double Ax[] = { 2., 3., 3., -1., 4., 4., -3., 1., 2., 2., 6., 1. };
  double B[] = { 8., 45., -3., 3., 19. };
  double X[] = { 0., 0., 0., 0., 0. };

  double* null = (double*)NULL;

  void* Symbolic;
  umfpack_di_symbolic(n, n, Ap, Ai, Ax, &Symbolic, null, null);

  void* Numeric;
  umfpack_di_numeric(Ap, Ai, Ax, Symbolic, &Numeric, null, null);

  umfpack_di_free_symbolic(&Symbolic);

  umfpack_di_solve(UMFPACK_A, Ap, Ai, Ax, X, B, Numeric, null, null);
  umfpack_di_free_numeric(&Numeric);

  for (int i = 0; i < n; i++)
    printf("X [%d] = %.1f\n", i, X[i]);
}