【字符串】统计一行字符串中有多少单词？

注意空格的情况：连续多个空格；一行字符串的尾部有空格。

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        while (scanner.hasNextLine()) {

            String input = scanner.nextLine();
            int result = Main.count(input);
            System.out.println("count:" + result);
        }
    }

    public static int count(String str) {

        int num = 0;
        int flag = 0;
        char[] array = str.toCharArray();

        for (int i = 0; i < array.length; i++) {
            if (array[i] == ' ' && flag == 0) {
                num++;
                flag = 1;
            } else if (array[i] != ' ') {
                flag = 0;
            }
        }

        if (' ' == array[array.length - 1]) {
            return num;
        } else {
            return num + 1;
        }
    }
}