[examples] a few rewordings

examples/ntzgaudet/README.md

@@ -7,6 +7,8 @@ To compile and run this Leo program, run:
 leo run
 ```
 
+## The Algorithm
+
 This algorithm is described in "Hacker's Delight, 2nd edition" by Henry
 S. Warren, section 5-4, section 5-24, as interesting due to being branch-free,
 not using table lookups, and having parallelism.  It is attributed to Dean Gaudet
@@ -19,11 +21,12 @@ written as `0u32.sub_wrapped(x)`.  The result is stored in `y`.
 Then we compute six intermediate variables that count different numbers
 of trailing zeros.  The first variable, `bz`, just counts 1 if `y` is completely zero.
 
-Then we do binary search in parallel, using 5 masks, each looking at
-a different subset of 16 bits.  For example, `b4` counts 16 if the low
-16 bits are zero and counts zero otherwise.  Then `b3` uses a mask
-`y & 0x00FF00FF` to count eight 0-bits if the result is zero and zero 0-bits otherwise.
-The masks for `b2`, `b1`, and `b0` potentially count four, two, and one 0-bits similarly.
+To get the other five variables, we do binary search in parallel, using 5 masks,
+each looking at a different symmetric pattern of 16 bits.  For example, `b4` counts 16 if
+the low 16 bits are zero and counts zero otherwise.  Then `b3` uses a mask `y &
+0x00FF00FF` to count eight 0-bits if the result is zero and zero 0-bits
+otherwise.  The masks for `b2`, `b1`, and `b0` can count four, two, and
+one 0-bits similarly.
 
 The varables `bz, b4, .., b0` are all independent, and their values are added up
 for the result.

examples/ntzloops/README.md

@@ -24,7 +24,8 @@ expressed in Leo as `!x & x.sub_wrapped(1u32);`.
 Then we simply count the 1-bits by right shifting until `x` is zero and
 counting the number of shifts using the variable `n`.
 
-To get the effect of a while loop in Leo, one must use a `for` loop with the maximum
-possible number of iterations, and then check the while-analogous condition within
-the for loop.  Once the condition is false, the loop completes but the `if` statement
-inside the loop prevents any further operations.
+To get the effect of a while loop in Leo, one must use a `for` loop with the
+enough iterations to accommodate all possible inputs, and then check the
+while condition within the for loop.  Once the condition is false, the
+loop continues until finished but the `if` statement inside the loop prevents
+any further operations.

examples/ntzreisers/README.md

@@ -21,7 +21,7 @@ divide the 33 arguments 0, 1, 2, ..., 2**31, the remainder is different for
 each argument. This constant is 37.
 
 In the algorithm, the remainder is used as an index into a table of size 37,
-with 4 entries unused.  The table's values were chosen so that they gave the
+with 4 entries unused.  The table's values were chosen so that they give the
 correct number of trailing zeros for the inputs.
 
 This algorithm was proposed by John Reiser in the comp.arch.arithmetic newsgroup