26 lines
440 B
C++
26 lines
440 B
C++
#include <bits/stdc++.h>
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using namespace std;
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int main(int argc, char const *argv[]) {
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double eps;
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double pi;
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double sum = 0;
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int sign = 1;
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scanf("%lf", &eps);
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for (int i = 0;; i++) {
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double x = sign / (sqrt(3) * pow(3, i) * (2 * i + 1));
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sum += sign / (sqrt(3) * pow(3, i) * (2 * i + 1));
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sign = -sign;
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if (1 / (sqrt(3) * pow(3, i) * (2 * i + 1)) < eps)
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break;
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}
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pi = 6 * sum;
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printf("pi=%f\n", pi);
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return 0;
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} |