public static void main (String[] args) { int sum = 0; try (BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)) { while(sum == 0) { System.out.print("3桁の数値を入力してください: "); String line = reader.readLine(); for(int i = 0; i < line.length(); i++) { char ch = line.charAt(i); try { sum += Character.getNumericValue(ch); } catch(NumberFormatException e) { System.out.println("数字の形式が
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