NAG Library Manual, Mark 28.5
```/* F07UE_P0W_F C++ Header Example Program.
*
* Copyright 2022 Numerical Algorithms Group.
* Mark 28.5, 2022.
*/

#include <iostream>
#include <nag.h>
#include <nagx04.h>
#include <stdio.h>
#include <string>
using namespace std;

int main()
{
int               exit_status = 0;
Integer           ifail = 0;

cout << "F07UE_P0W_F C++ Header Example Program Results\n\n";
// Skip heading in data file
string mystr;
getline(cin, mystr);

// Read problem size and number of right-hand-sides
Integer n, nrhs;
cin >> n;
cin >> nrhs;

// Allocate arrays containing A and its factorized form, B
// and the solution X.
double *a = 0, *b = 0;
a = new double[n * n];
b = new double[n * nrhs];

// Read the lower triangular matrix A, register and copy
for (int i = 0; i < n; ++i)
{
Integer l = 0;
for (int j = 0; j <= i; ++j)
{
Integer k = l + i;
cin >> a[k];
l = l + (n - j - 1);
}
}
// Read the right-hand-sides, register and copy
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < nrhs; ++j)
{
int k = i + j * n;
cin >> b[k];
}
}

// Solve the system
ifail = 0;

// Print solution
cout << endl;
NagError fail;
INIT_FAIL(fail);
x04cac(Nag_ColMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, nrhs, b, n,
"  Solution", 0, &fail);

delete[] a;
delete[] b;
return exit_status;
}
```