UPC: Difference between revisions
→{{header|Julia}}
Line 1,165:
It may be desirable to format the result differently, but that's currently not a part of the task definition.
=={{header|Java}}==
{{trans|Kotlin}}
<lang java>import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.stream.Collectors;
public class UPC {
private static final int SEVEN = 7;
private static final Map<String, Integer> LEFT_DIGITS = Map.of(
" ## #", 0,
" ## #", 1,
" # ##", 2,
" #### #", 3,
" # ##", 4,
" ## #", 5,
" # ####", 6,
" ### ##", 7,
" ## ###", 8,
" # ##", 9
);
private static final Map<String, Integer> RIGHT_DIGITS = LEFT_DIGITS.entrySet()
.stream()
.collect(Collectors.toMap(
entry -> entry.getKey()
.replace(' ', 's')
.replace('#', ' ')
.replace('s', '#'),
Map.Entry::getValue
));
private static final String END_SENTINEL = "# #";
private static final String MID_SENTINEL = " # # ";
private static void decodeUPC(String input) {
Function<String, Map.Entry<Boolean, List<Integer>>> decode = (String candidate) -> {
int pos = 0;
var part = candidate.substring(pos, pos + END_SENTINEL.length());
List<Integer> output = new ArrayList<>();
if (END_SENTINEL.equals(part)) {
pos += END_SENTINEL.length();
} else {
return Map.entry(false, output);
}
for (int i = 1; i < SEVEN; i++) {
part = candidate.substring(pos, pos + SEVEN);
pos += SEVEN;
if (LEFT_DIGITS.containsKey(part)) {
output.add(LEFT_DIGITS.get(part));
} else {
return Map.entry(false, output);
}
}
part = candidate.substring(pos, pos + MID_SENTINEL.length());
if (MID_SENTINEL.equals(part)) {
pos += MID_SENTINEL.length();
} else {
return Map.entry(false, output);
}
for (int i = 1; i < SEVEN; i++) {
part = candidate.substring(pos, pos + SEVEN);
pos += SEVEN;
if (RIGHT_DIGITS.containsKey(part)) {
output.add(RIGHT_DIGITS.get(part));
} else {
return Map.entry(false, output);
}
}
part = candidate.substring(pos, pos + END_SENTINEL.length());
if (!END_SENTINEL.equals(part)) {
return Map.entry(false, output);
}
int sum = 0;
for (int i = 0; i < output.size(); i++) {
if (i % 2 == 0) {
sum += 3 * output.get(i);
} else {
sum += output.get(i);
}
}
return Map.entry(sum % 10 == 0, output);
};
Consumer<List<Integer>> printList = list -> {
var it = list.iterator();
System.out.print('[');
if (it.hasNext()) {
System.out.print(it.next());
}
while (it.hasNext()) {
System.out.print(", ");
System.out.print(it.next());
}
System.out.print(']');
};
var candidate = input.trim();
var out = decode.apply(candidate);
if (out.getKey()) {
printList.accept(out.getValue());
System.out.println();
} else {
StringBuilder builder = new StringBuilder(candidate);
builder.reverse();
out = decode.apply(builder.toString());
if (out.getKey()) {
printList.accept(out.getValue());
System.out.println(" Upside down");
} else if (out.getValue().size() == 12) {
System.out.println("Invalid checksum");
} else {
System.out.println("Invalid digit(s)");
}
}
}
public static void main(String[] args) {
var barcodes = List.of(
" # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # ",
" # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # ",
" # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # ",
" # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # ",
" # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # ",
" # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # ",
" # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # ",
" # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # ",
" # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # ",
" # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # "
);
barcodes.forEach(UPC::decodeUPC);
}
}</lang>
{{out}}
<pre>[9, 2, 4, 7, 7, 3, 2, 7, 1, 0, 1, 9]
[4, 0, 3, 9, 4, 4, 4, 4, 1, 0, 5, 0]
[8, 3, 4, 9, 9, 9, 6, 7, 6, 7, 0, 6] Upside down
[9, 3, 9, 8, 2, 5, 1, 5, 8, 8, 1, 1] Upside down
Invalid digit(s)
[3, 1, 6, 3, 1, 3, 7, 1, 8, 7, 1, 7] Upside down
[2, 1, 4, 5, 7, 5, 8, 7, 5, 6, 0, 8]
[8, 1, 8, 7, 7, 8, 8, 4, 1, 8, 1, 3] Upside down
[7, 0, 6, 4, 6, 6, 7, 4, 3, 0, 3, 0]
[6, 5, 3, 4, 8, 3, 5, 4, 0, 4, 3, 5]</pre>
=={{header|Julia}}==
| |||