

实现代码:
java
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int l = scanner.nextInt();
int r = scanner.nextInt();
int n = 0;
for(int i = l ; i <= r; i ++){
if(i % 2 == 0){
n ++;
}
}
System.out.println(n);
scanner.close();
}