```/* E04US_P0W_F C++ Header Example Program.
*
* Copyright 2019 Numerical Algorithms Group.
* Mark 27, 2019.
*/

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

extern "C"
{
static void NAG_CALL objfun(void* &ad_handle, Integer &mode,
const Integer &m, const Integer &n,
const Integer &ldfj, const Integer &needfi,
const double x[], double f[], double fjac[],
const Integer &nstate, Integer iuser[],
double ruser[]);
static void NAG_CALL confun(void* &ad_handle, Integer &mode,
const Integer &ncnln, const Integer &n,
const Integer &ldcj, const Integer needc[],
const double x[], double c[], double cjac[],
const Integer &nstate, Integer iuser[],
double ruser[]);
}

int main(void)
{
// Scalars
int               exit_status = 0;

cout << "E04US_P0W_F C++ Header Example Program Results\n\n";

Integer ifail = 0;

// Skip first line of data file
string mystr;
getline (cin, mystr);

Integer m, n, nclin, ncnln;
cin >> m;
cin >> n;
cin >> nclin;
cin >> ncnln;

Integer liwork = 3*n + nclin + 2*ncnln;
Integer lda = nclin, sda = n, ldcj = ncnln, ldfj = m, ldr = n;
Integer lwork;

lwork = 20*n + m*(n+3);
if (nclin>0) {
lwork = lwork + 2*n*n + 11*nclin;
}
if (ncnln>0) {
lwork = lwork + n*nclin + (2*n+21)*ncnln;
}
Integer lb = n + nclin + ncnln;
double  *a=0,    *bl=0,     *bu=0, *y=0, *c=0, *cjac=0, *f=0;
double  *fjac=0, *clamda=0, *r=0,  *x=0, *work=0, *rwsav=0;
Integer *istate=0, *iwork=0, *iwsav=0;
logical *lwsav=0;
a      = new double  [lda*sda];
bl     = new double  [lb];
bu     = new double  [lb];
y      = new double  [m];
c      = new double  [ncnln];
cjac   = new double  [ncnln*n];
f      = new double  [m];
fjac   = new double  [m*n];
clamda = new double  [lb];
r      = new double  [ldr*n];
x      = new double  [n];
work   = new double  [lwork];
rwsav  = new double  [475];
lwsav  = new logical [120];
istate = new Integer [lb];
iwork  = new Integer [liwork];
iwsav  = new Integer [610];

// Read problem parameters and register for differentiation
for (int i=0; i<nclin; i++) {
for (int j=0; j<sda; j++) {
Integer k = i + j*nclin;
cin >> a[k];
}
}
for (int i=0; i<m; i++) {
cin >> y[i];
}
for (int i=0; i<lb; i++) {
cin >> bl[i];
}
for (int i=0; i<lb; i++) {
cin >> bu[i];
}
for (int i=0; i<n; i++) {
cin >> x[i];
}

double ruser[44] = {8.0,8.0,10.0,10.0,10.0,10.0,12.0,12.0,12.0,12.0,14.0,14.0,
14.0,16.0,16.0,16.0,18.0,18.0,20.0,20.0,20.0,22.0,22.0,
22.0,24.0,24.0,24.0,26.0,26.0,26.0,28.0,28.0,30.0,30.0,
30.0,32.0,32.0,34.0,36.0,36.0,38.0,38.0,40.0,42.0};
// Initialize sav arrays
ifail = 0;
char cwsav[1];
e04wb_p0w_f_("E04USA",cwsav,1,lwsav,120,iwsav,610,rwsav,475,ifail,6,1);

// Solve the problem
Integer iter, iuser[1];
double  objf;
ifail = -1;
confun,objfun,iter,istate,c,cjac,f,fjac,clamda,objf,r,
x,iwork,liwork,work,lwork,iuser,ruser,lwsav,iwsav,rwsav,ifail);

// Primal results
cout.setf(ios::scientific,ios::floatfield);
if (ifail==0 || ifail>1) {
cout.precision(4);
cout << "\n Optimal objective function value = ";
cout.width(12); cout << objf;
cout << "\n Solution point = ";
for (int i=0; i<n; i++) {
cout.width(12); cout << x[i];
}
cout << endl;
} else {
cout << "e04us_p0w_f_ failed with ifail = " << ifail << endl;
}

delete [] a;
delete [] bl;
delete [] bu;
delete [] y;
delete [] c;
delete [] cjac;
delete [] f;
delete [] fjac;
delete [] clamda;
delete [] r;
delete [] x;
delete [] work;
delete [] rwsav;
delete [] lwsav;
delete [] istate;
delete [] iwork;
delete [] iwsav;
return exit_status;
}

static void NAG_CALL objfun(void* &ad_handle, Integer &mode,
const Integer &m, const Integer &n,
const Integer &ldfj, const Integer &needfi,
const double x[], double f[], double fjac[],
const Integer &nstate, Integer iuser[],
double ruser[])
{
double x1, x2;
x1 = x[0];
x2 = x[1];

if (mode==0 && needfi>0) {
f[needfi-1] = x1 + (0.49-x1)*exp(-x2*(ruser[needfi-1]-8.0));
} else {
for (int i=0; i<m; ++i) {
double ai   = ruser[i] - 8.0;
double temp = exp(-x2*ai);

if (mode==0 || mode==2) {
f[i] = x1 + (0.49-x1)*temp;
}
if (mode==1 || mode==2) {
fjac[i] = 1.0 - temp;
fjac[i+m] = -(0.49-x1)*ai*temp;
}
}
}
return;
}
static void NAG_CALL confun(void* &ad_handle, Integer &mode,
const Integer &ncnln, const Integer &n,
const Integer &ldcj, const Integer needc[],
const double x[], double c[], double cjac[],
const Integer &nstate, Integer iuser[],
double ruser[])
{
if (nstate==1) {
for (int i = 0; i<ncnln*n; ++i) {
cjac[i] = 0.0;
}
}
if (needc[0]>0) {
if (mode==0 || mode==2) {
c[0] = -0.09 - x[0]*x[1] + 0.49*x[1];
}
if (mode==1 || mode==2) {
cjac[0] = -x[1];
cjac[ncnln] = -x[0] + 0.49;
}
}
return;
}
```