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/*
Challenge 006
Challenge #2
Create a script to calculate Ramanujan's constant with at least 32 digits of
precision. Find out more about it here.
The standard IEEE 754 double-precision binary floating-point format: binary64
gives only 15 to 17 significant decimal digits
*/
#include <iostream>
#include <gmp.h>
#include <mpfr.h>
int main() {
mpfr_set_default_prec(256); // 107 bits needed to represent 32 decimal digits
mpfr_t pi, e, k;
mpfr_inits(pi, e, k, NULL);
mpfr_const_pi(pi, MPFR_RNDN);
mpfr_set_str(e, "163", 10, MPFR_RNDN); // e = 163
mpfr_sqrt(e, e, MPFR_RNDN); // e = sqr(163)
mpfr_mul(e, pi, e, MPFR_RNDN); // e = pi*sqr(163)
mpfr_exp(k, e, MPFR_RNDN); // k = e^(pi*sqr(163))
mpfr_printf("%32.12Rf\n", k); // 18.12 = 32 precision
mpfr_clears(pi, e, k, NULL);
}
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