blob: 74eec8fc78465b2da606f553933db3f73b393278 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/*
Week 135:
https://theweeklychallenge.org/blog/perl-weekly-challenge-135
Task #1: Middle 3-digits
You are given an integer.
Write a script find out the middle 3-digits of the given integer, if possible otherwise throw sensible error.
*/
class MiddleThreeDigits {
public static void main(String[] args) {
String p = System.getProperty("number", "1234567");
Pattern pattern = Pattern.compile("\\-?\\d+");
if (pattern.matcher(p).find()) {
int n = Math.abs(Integer.parseInt(p));
int l = countDigits(n);
if (l == 1) {
System.out.println("ERROR: Too short.");
}
else if (l % 2 == 0) {
System.out.println("ERROR: Even number of digists.");
}
else {
int i = (l / 2) - 1;
System.out.println(String.valueOf(n).substring(i, i+3));
}
}
else {
System.out.println("ERROR: Invalid number.");
}
}
public static int countDigits(int n) {
int l = 0;
for(; n != 0; n /= 10, ++l);
return l;
}
}
|
