Find the loop invariant of the loop in this code.

% You are given an array x of real numbers, indexed from 0 to n-1

  real sumPositive = 0;
  int i = 0;
  while (i < n)
    {
     if (x[i] > 0)
      sumPositive += x[i];
     i++;
    }
  cout << sumPositive << endl;

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  This code has two loops.  Find the loop invariant of each.

% You are given an array x of real numbers, indexed from 0 to n-1

  int i = 0;
  while (i < n)
    {
     int j = i+1;
     while (j < n)
       {
        if (x[i] > x[j])
         {
          real y = x[i];
          x[i] = x[j];
          x[j] = y;
         }
        j++;
       }
     i++;
    }

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  Find the loop invariant of the loop in this code.

  real x;
  int n;
  cin >> x;
  cin >> n;
% Input condition: n >= 0
  real y = x;
  int m = n;
  real result = 1.0;
  while (m > 0)
   if (m % 2)
    {
     m = m-1;
     result = result*y;
    }
   else
    {
     m = m/2;
     y = y*y;
    }
  cout << result << endl;