回答編集履歴
1
コード修正
answer
CHANGED
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@@ -43,37 +43,37 @@
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43
43
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`4+2=` のようにスペースなしにしたい場合は少し面倒になります。
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44
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```Java
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45
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import java.util.Scanner;
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46
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-
import java.util.regex.MatchResult;
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46
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import java.util.regex.*; // Pattern, MatchResult;
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47
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class Test {
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49
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-
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49
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public static void main(String[] args) {
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50
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-
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50
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Scanner sc = new Scanner(System.in);
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51
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Pattern pat = Pattern.compile("(\d+)\s*(.)\s*(\d+)\s*=");
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51
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-
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52
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while (true) {
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52
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-
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System.out.print(">> ");
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53
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if (!sc.hasNextLine()) break;
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54
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-
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String line = sc.nextLine();
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Scanner sc2 = new Scanner(line);
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-
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try {
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sc2.findInLine(pat);
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-
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MatchResult r = sc2.match();
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if (r.groupCount() != 3) throw new Exception();
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int x = Integer.parseInt(r.group(1));
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-
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int y = Integer.parseInt(r.group(3));
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int z = 0;
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63
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switch (r.group(2)) {
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-
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64
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case "+": z = x + y; break;
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65
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-
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case "-": z = x - y; break;
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66
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-
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case "*": z = x * y; break;
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-
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case "/": z = x / y; break;
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-
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}
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-
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System.out.println(z);
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}
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catch (Exception e) {
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System.out.println(" Error");
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-
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}
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-
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sc2.close();
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-
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}
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-
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sc.close();
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-
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}
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}
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```
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