32 lines
610 B
C++
32 lines
610 B
C++
#include <iostream>
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#include <cmath>
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#include <numeric>
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#include <ios>
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#include <cstdlib>
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double compute_serie_3_term(unsigned long n) {
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return -((double)(2*n+1))/(double)(2*n+3);
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}
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double compute_serie_3(double err) {
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unsigned long k = 0;
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double ak = 1;
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double acc = 1;
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while (err < 4*std::abs(ak)) {
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ak *= compute_serie_3_term(k++);
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acc += ak;
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}
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std::cout << k << " " << 4*acc << " " << std::abs(3.14159265358979324$$ - 4*acc) << '\n';
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return 4*acc;
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}
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int main(int, char **argv) {
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const double err = std::pow(10.0, -std::atof(argv[1]));
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std::cout.precision(17);
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compute_serie_3(err);
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}
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