為什么System.out.print（rev）;上有錯誤？

Question

public static void main(String[] args) {
    // TODO Auto-generated method stub

    String rev = "";
    String input = "Hello World";
    int length = input.length();
    for (int i = length - 1; 1 >= 0; i--){

    rev = rev + input.charAt(i);    

}
System.out.print(rev);

Answer 1

假設您已經復制並粘貼了該塊和代碼，則該錯誤是因為System.out.print(rev); 已放置在main()功能塊之外。

Answer 2

String str = "Welcome Java";
char[] strArray = str.toCharArray();

for (int i = strArray.length-1; i >=0 ; i--) {
    System.out.print(strArray[i]);
}