```/* nag_stat_inv_cdf_students_t_vector (g01tbc) Example Program.
*
* Copyright 2019 Numerical Algorithms Group.
*
* Mark 27.0, 2019.
*/
#include <stdio.h>
#include <nag.h>

int main(void)
{
/* Integer scalar and array declarations */
Integer ltail, lp, ldf, i, lout;
Integer *ivalid = 0;
Integer exit_status = 0;

/* NAG structures */
NagError fail;
Nag_TailProbability *tail = 0;

/* Double scalar and array declarations */
double *p = 0, *df = 0, *t = 0;

/* Character scalar and array declarations */
char ctail;

/* Initialize the error structure to print out any error messages */
INIT_FAIL(fail);

printf("nag_stat_inv_cdf_students_t_vector (g01tbc) Example Program Results\n\n");

/* Skip heading in data file */
scanf("%*[^\n] ");

/* Read in the input vectors */
scanf("%" NAG_IFMT "%*[^\n] ", &ltail);
if (!(tail = NAG_ALLOC(ltail, Nag_TailProbability))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
for (i = 0; i < ltail; i++) {
scanf("%39s", ctail);
tail[i] = (Nag_TailProbability) nag_enum_name_to_value(ctail);
}
scanf("%*[^\n] ");
scanf("%" NAG_IFMT "%*[^\n] ", &lp);
if (!(p = NAG_ALLOC(lp, double)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
for (i = 0; i < lp; i++)
scanf("%lf", &p[i]);
scanf("%*[^\n] ");
scanf("%" NAG_IFMT "%*[^\n] ", &ldf);
if (!(df = NAG_ALLOC(ldf, double)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
for (i = 0; i < ldf; i++)
scanf("%lf", &df[i]);
scanf("%*[^\n] ");

/* Allocate memory for output */
lout = MAX(ltail, MAX(lp, ldf));
if (!(t = NAG_ALLOC(lout, double)) || !(ivalid = NAG_ALLOC(lout, Integer)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}

/* Calculate probability */
nag_stat_inv_cdf_students_t_vector(ltail, tail, lp, p, ldf, df, t, ivalid,
&fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_stat_inv_cdf_students_t_vector (g01tbc).\n%s\n",
fail.message);
exit_status = 1;
if (fail.code != NW_IVALID)
goto END;
}

/* Display title */
printf("          tail           p         df        t     ivalid\n");
printf("-----------------------------------------------------------\n");

/* Display results */
for (i = 0; i < lout; i++)
printf(" %17s    %6.3f    %6.1f   %7.4f    %3" NAG_IFMT "\n",
nag_enum_value_to_name(tail[i % ltail]), p[i % lp], df[i % ldf],
t[i], ivalid[i]);

END:
NAG_FREE(tail);
NAG_FREE(p);
NAG_FREE(df);
NAG_FREE(t);
NAG_FREE(ivalid);

return (exit_status);
}
```