0. Warmup

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/** Return the max value in A[start..end] */
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public int findMax(int[] a, int start, int end) {
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  currentMax = a[start]
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  for i in start+1..end:
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    if a[i] is bigger, update currentMax
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 return currentMax;
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}
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​
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/** Print the min of several subarrays of A
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 * Precondition: A.length >= 50. */
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public static void mins(A) {
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  for i in 0..50:
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      print(findMin(A, 0, i));
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}

1. Something new...

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public int f(int n) {
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  while (n > 0) {
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     System.out.println(n);
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     n = n/2;
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  }
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}

2. The merge method

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merge(A, start, end):
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  initialize i, j
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  B = deep copy of A
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  while neither uncopied segment is empty:
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      copy the smaller of B[i], B[j]
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           into A[k]
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      increment i or j
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      increment k
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  while one uncopied segment is empty:
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      copy the next element in the nonempty 
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          segment into A[k]
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      increment i or j
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      increment k

3. The partition method

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partition(A, start, end):
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  initialize i, j
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  while i < j:
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    if A[i] <= p:
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      swap(A, i, i-1)
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      i++
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    else:
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      swap(A, i, j-1)
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      j--

4. Radix sort

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LSDRadixSort(A):
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 create one bucket (queue) for each digit (0 to 9)
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 for each digit (least- to most-significant):
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    for v in A:
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      put v into the bucket based on digit
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    for each bucket, starting from smallest digit
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      while bucket is not empty:
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        move element to the next position in the array