Birthday Paradox

  public static double birthday(int n) {
      int dups = 0;
      double value = 0.0;
      
      for (int i = 0; i < n; i++) {
          boolean foundDup = false;
          int[] bday = new int[n];

          // assign birthdays to n people
          for (int i = 0; i < n; i++) {
              bday[i] = (int) (Math.random() * 365) + 1;
          }

          // check, to see if there's a duplicate
          for (int i = 1; i <= 365; i++) {
              int num = 0;
              for (int j = 0; j < n; j++) {
                  // comparing bdays to dates
                  if (bday[j] == i) {
                      num++;
                  }
              }
              if (num > 1) {
                  foundDup = true;
              }
              num = 0;
          }

          // count cases with duplicates
          if (foundDup == true) {
              dups++;
          }
      }
      double value = (double) dups / n;
      
      return (value*birthday(x));
    }
  

      

    

    double value = 0.0;
    int x = 0;


    if (n == 1) {
        return 0;
    }

    else {

     // P(N) = (1 - P(N-1)) * ((N-1)/365)

     value = 1 - birthday(n-1);
     x = (n-1)/365;

    }