GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it

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/****************************************************************************
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**
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*A  degree.c                    ANUPQ source                   Eamonn O'Brien
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**
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*Y  Copyright 1995-2001,  Lehrstuhl D fuer Mathematik,  RWTH Aachen,  Germany
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*Y  Copyright 1995-2001,  School of Mathematical Sciences, ANU,     Australia
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**
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*/
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#include "pq_defs.h"
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#include "pga_vars.h"
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#include "pq_functions.h"
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#include "constants.h"
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/* compute the number of allowable subgroups;
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   also, set up powers, offset, and inverses arrays */
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void compute_degree(struct pga_vars *pga)
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{
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   register int i;
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   register int maximum = 0;
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   pga->Degree = 0;
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   /* compute degree; store offset for each definition set */
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   for (i = 0; i < pga->nmr_def_sets; ++i) {
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      pga->offset[i] = pga->Degree;
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      /* this is a test to try to prevent integer overflow */
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      if (int_power(pga->p, pga->available[i]) > (INT_MAX - pga->Degree)) {
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         text(19, 0, 0, 0, 0);
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         if (!isatty(0))
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            exit(FAILURE);
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         else
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            return;
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      }
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      pga->Degree += int_power(pga->p, pga->available[i]);
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      if (maximum < pga->available[i])
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         maximum = pga->available[i];
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   }
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   /* store powers of prime */
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   pga->powers = allocate_vector(maximum + 1, 0, 0);
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   for (i = 0; i <= maximum; ++i)
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      pga->powers[i] = int_power(pga->p, i);
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   /* store inverses of 1 .. p - 1 */
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   pga->inverse_modp = allocate_vector(pga->p, 0, 0);
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   for (i = 1; i < pga->p; ++i)
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      pga->inverse_modp[i] = invert_modp(i, pga->p);
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   if (pga->print_degree)
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      printf("Degree of permutation group is %d\n", pga->Degree);
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}
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