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#include "precision.h"
/*
* Raise to precision power mod m
*/
precision ppowmod(u, v, m)
precision u, v, m;
{
precision j = pUndef, i = pUndef, n = pUndef;
(void) pparm(m);
pset(&i, pparm(u));
pset(&n, pparm(v));
pset(&j, pone);
do {
if (podd(n)) {
pset(&j, pmod(pmul(i, j), m));
}
pset(&n, phalf(n));
if (peqz(n)) break;
pset(&i, pmod(pmul(i, i), m));
} while (1);
pdestroy(i); pdestroy(n);
pdestroy(u); pdestroy(v); pdestroy(m);
return presult(j);
}
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