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Issue 238 fixed: add comments to code block in 3.4 #242

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Merged
pearcej merged 1 commit into from
Jul 28, 2026
Merged

Issue 238 fixed: add comments to code block in 3.4 #242

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13 changes: 8 additions & 5 deletions source/ch3_javadatatypes.ptx
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Original file line number Diff line number Diff line change
Expand Up @@ -783,13 +783,16 @@ public class Histo {

<program xml:id="java-array" interactive="activecode" language="java" datafile="test.dat">
<code>
import java.util.Scanner;
import java.io.File;
import java.io.IOException;
import java.util.Scanner; // import the Scanner class to read input from the user
import java.io.File; // import the File class to read from files
import java.io.IOException; // import the IOException class to handle file input/output exceptions
/**
* Program to read numbers from a file and produce a histogram using arrays in Java.
*/
public class HistoArray {
public static void main(String[] args) {
Scanner data = null;
Integer[] count = {0,0,0,0,0,0,0,0,0,0};
Integer[] count = {0,0,0,0,0,0,0,0,0,0}; // create an array of 10 integers initialized to 0
Integer idx;
try {
data = new Scanner(new File("test.dat"));
Expand All @@ -801,7 +804,7 @@ public class HistoArray {
}
while(data.hasNextInt()) {
idx = data.nextInt();
count[idx] = count[idx] + 1;
count[idx] = count[idx] + 1; // increment the count for the number read from the file, using array indexing
}
idx = 0;
for(Integer i : count) {
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