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  1. #include <iostream>
  2. #include <vector>
  3. #include <cmath>
  4. #include <random>
  5. #include <chrono>
  6. #include <iomanip>
  7.  
  8. int main() {
  9.     unsigned seed = std::chrono::high_resolution_clock::now().time_since_epoch().count();
  10.     std::mt19937 generator(seed);
  11.     std::uniform_real_distribution<double> distribution(0.0, 1.0);
  12.  
  13.     std::vector<int> N_values = {1000, 10000, 100000};
  14.  
  15.     for (int N : N_values) {
  16.         long long points_inside_circle = 0;
  17.  
  18.         for (int i = 0; i < N; ++i) {
  19.             double x = distribution(generator);
  20.             double y = distribution(generator);
  21.             if ((x * x + y * y) <= 1.0) {
  22.                 points_inside_circle++;
  23.             }
  24.         }
  25.  
  26.         double estimated_pi = 4.0 * static_cast<double>(points_inside_circle) / N;
  27.         double error = std::fabs(M_PI - estimated_pi);
  28.  
  29.         std::cout << "For N = " << N << ":\n";
  30.         std::cout << "  Estimated Pi = " << std::fixed << std::setprecision(10) << estimated_pi << "\n";
  31.         std::cout << "  Error        = " << std::setprecision(10) << error << "\n\n";
  32.     }
  33.  
  34.     return 0;
  35. }
Success #stdin #stdout 0.01s 5320KB
comments (?)
stdin 
Standard input is empty
stdout 
For N = 1000:
  Estimated Pi = 3.0760000000
  Error        = 0.0655926536

For N = 10000:
  Estimated Pi = 3.1464000000
  Error        = 0.0048073464

For N = 100000:
  Estimated Pi = 3.1406400000
  Error        = 0.0009526536
https://ideone.com/P404gh
language:
C++ (gcc 8.3)
created:
6 days ago
visibility:
public

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