```/* nag_zero_cont_func_brent_rcomm (c05azc) Example Program.
*
* Copyright 2017 Numerical Algorithms Group.
*
* Mark 26.2, 2017.
*/

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <math.h>
#include <nagc05.h>

int main(void)
{
/* Scalars */
Integer exit_status = 0;
double fx, tolx, x, y;
Integer ind;
Nag_ErrorControl ir;
/* Arrays */
double c[17];
NagError fail;

INIT_FAIL(fail);

printf("nag_zero_cont_func_brent_rcomm (c05azc) Example Program Results\n");
printf("\n Iterations\n");

tolx = 1e-05;
x = 0.0;
y = 1.0;
ir = Nag_Mixed;
ind = 1;
fx = 0.0;
/* nag_zero_cont_func_brent_rcomm (c05azc).
* Locates a simple zero of a continuous function.
* Reverse communication.
*/
while (ind != 0) {
nag_zero_cont_func_brent_rcomm(&x, &y, fx, tolx, ir, c, &ind, &fail);

if (ind != 0) {
fx = exp(-x) - x;
printf(" x = %8.5f   fx = %13.4e   ind = %2" NAG_IFMT "\n", x, fx, ind);
}
}

if (fail.code == NE_NOERROR) {
printf("\n Solution\n");
printf(" x = %8.5f   y = %8.5f\n", x, y);
}
else {
printf("%s\n", fail.message);
if (fail.code == NE_PROBABLE_POLE ||
fail.code == NW_TOO_MUCH_ACC_REQUESTED) {
printf(" x = %8.5f   y = %8.5f\n", x, y);
}
exit_status = 1;
goto END;
}

END:
return exit_status;
}
```