From bbafedef8eb2b11ed745e6ebfe16e387981d6a24 Mon Sep 17 00:00:00 2001
From: "Dr. Martin Goik" <goik@hdm-stuttgart.de>
Date: Sun, 29 Apr 2018 19:43:34 +0200
Subject: [PATCH] Removing duplicate sum exercise

---
 Doc/Sd1/statements.xml | 86 ++++++------------------------------------
 1 file changed, 11 insertions(+), 75 deletions(-)

diff --git a/Doc/Sd1/statements.xml b/Doc/Sd1/statements.xml
index d524786b1..b065156e1 100644
--- a/Doc/Sd1/statements.xml
+++ b/Doc/Sd1/statements.xml
@@ -3359,21 +3359,14 @@ System.out.println("1 + ... + " + limit + " = " + sum);        </programlisting>
             <qandaentry>
               <question>
                 <para>In <xref linkend="sd1_fig_loopCalculations"/> for a
-                given value of limit only the first and last summands will
-                show up: We just see <code>1 + ... + 5 = 15</code> rather than
+                given value of limit only the first and last summand will show
+                up: We just see <code>1 + ... + 5 = 15</code> rather than
                 <code>1 + 2 + 3 + 4 + 5 = 15</code>.</para>
 
-                <para>Even worse:</para>
+                <para>If <code language="java">limit</code> is equal to one
+                the visible result is even worse:</para>
 
-                <glosslist>
-                  <glossentry>
-                    <glossterm>limit = 1:</glossterm>
-
-                    <glossdef>
-                      <screen>1 + ... + 1 = 1</screen>
-                    </glossdef>
-                  </glossentry>
-                </glosslist>
+                <screen>1 + ... + 1 = 1</screen>
 
                 <para>Modify the code accordingly to correct these flaws /
                 shortcomings.</para>
@@ -3408,7 +3401,7 @@ System.out.println(" = " + sum);</programlisting>
 
                 <programlisting language="none">for (int i = 1; i &lt;= limit; i++) {
   System.out.print(i);
-  <emphasis role="red">if (i &lt; limit)</emphasis> {
+  <emphasis role="red">if (i &lt; limit)</emphasis> { <emphasis role="bold">// Avoid '+' for the last value</emphasis>
     System.out.print(" + ");
   }
   sum += i;
@@ -3424,69 +3417,12 @@ System.out.println(" = " + sum);</programlisting>
                 1</code> as well:</para>
 
                 <screen>1 = 1</screen>
-              </answer>
-            </qandaentry>
-          </qandadiv>
-        </qandaset>
-
-        <qandaset defaultlabel="qanda" xml:id="sd1_qanda_allSummands">
-          <title>Showing all constituents of a sum</title>
-
-          <qandadiv>
-            <qandaentry>
-              <question>
-                <para>In <xref linkend="sd1_fig_loopCalculations"/> the
-                resulting output was:</para>
-
-                <screen>1 + ... + 5 = 15</screen>
-
-                <para>Modify the code to show all contributing values
-                <computeroutput>1 + 2 + 3 + 4 + 5 = 15</computeroutput>
-                instead.</para>
-              </question>
-
-              <answer>
-                <para>First we need to print all values of our loop variable
-                <code language="java">i</code>:</para>
-
-                <programlisting language="java">for (int i = 1; i &lt;= limit; i++) {
-    System.out.print(i + " + ");
-    sum += i;
-}</programlisting>
-
-                <para>This yields <computeroutput>1 + 2 + 3 + 4 + 5
-                +</computeroutput>. Notice the last <quote><code
-                language="java">+</code></quote> operator: To avoid this
-                operator being printed we may split our print statement and
-                add an <code language="java">if</code> guard inside our
-                loop:</para>
-
-                <programlisting language="java">for (int i = 1; i &lt;= limit; i++) {
-    System.out.print(i);
-    <emphasis role="bold">if (i &lt; limit) { // Do not print last value</emphasis>
-        System.out.print(" + ");
-    <emphasis role="bold">}</emphasis>
-    sum += i;
-}</programlisting>
-
-                <para>This leaves us with <computeroutput>1 + 2 + 3 + 4 +
-                5</computeroutput>. The only bit missing is a final print
-                statement supplying the last operand and the sum in
-                question:</para>
-
-                <programlisting language="java">for (int i = 1; i &lt;= limit; i++) {
-    System.out.print(i);
-    if (i &lt; limit) { // Do not print last value
-        System.out.print(" + ");
-    }
-    sum += i;
-}
-<emphasis role="bold">System.out.println(" = " + sum);</emphasis></programlisting>
 
-                <para>Instead of filtering a <quote><code
+                <para>Instead of filtering the very last <quote><code
                 language="java">+</code></quote> operator we may as well
-                terminate our loop earlier and move the last operand to the
-                second print statement:</para>
+                terminate our loop one step earlier and move the last operand
+                to the second print statement leaving us with an identical
+                result:</para>
 
                 <programlisting language="java">int limit = 5;
 int sum = 0;
@@ -3495,7 +3431,7 @@ for (int i = 1; i &lt; limit; i++) {
     System.out.print(i + " + ");
     sum += i;
 }
-sum += limit; // accounting for last term missing
+sum += limit; // account for last term
 
 System.out.println(limit + " = " + sum);</programlisting>
               </answer>
-- 
GitLab