Classic Insertion Sort

T A[n];   // array of size n
T t;      // local variable
int i, j; // loop control variables
for (i = 1; i < n; ++i)
{
  t = A[i];
  for (j = i; j > 0 && t < A[j - 1]; --j)
    A[j] = A[j - 1];
  A[j] = t;
}

• in place
• stable
• WCRT = 1 + 2 + ... + n = Θ(n²)
• BCRT = 1 + 1 + ... + 1 = Θ(n)
• Runtime approaches Θ(n) as input data nears being sorted
• generic algorithm g_insertion_sort(Iter beg, Iter end)
• requires bidirectional iterators