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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. int main() {
  5.     srand(time(0));
  6.  
  7.     int sizes[] = {1000, 10000, 100000};
  8.  
  9.     for (int n : sizes) {
  10.         int in = 0;
  11.         for (int i = 0; i < n; i++) {
  12.             double x = (double)rand() / RAND_MAX;
  13.             double y = (double)rand() / RAND_MAX;
  14.             if (x*x + y*y <= 1.0) in++;
  15.         }
  16.         double pi = 4.0 * in / n;
  17.         cout << n << "\t" << in << "\t" << pi << endl;
  18.     }
  19.  
  20.     return 0;
  21. }
  22.  
  23. /*
  24. Q1. How does the estimate change with larger N?
  25. = As N increases, the estimate becomes more accurate and closer to π.
  26.  
  27. Q2. How close does it get to actual π?
  28. = With N=1000, error ≈ ±0.1; N=10000, error ≈ ±0.03; N=100000, error ≈ ±0.01. 
  29. Larger N improves the approximation to 3.14159.
  30. */
  31.  
Success #stdin #stdout 0.01s 5328KB
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stdin
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Standard input is empty
stdout
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1000	780	3.12
10000	7838	3.1352
100000	78608	3.14432
https://ideone.com/0Gct1S
language:
C++ (gcc 8.3)
created:
6 days ago
visibility:
public

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