题解 | #游游的整数切割#

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        
        // 读取输入字符串
        String s = scanner.nextLine();
        
        int ans = 0;
        int last = s.charAt(s.length() - 1) - '0';
        
        for (int i = 0; i < s.length() - 1; i++) {
            int current = s.charAt(i) - '0';
            if ((current + last) % 2 == 0) {
                ans++;
            }
        }
        
        // 输出结果
        System.out.println(ans);
        
        scanner.close();
    }
}