2019趣头条笔试题——从1到n整数中2出现的次数

趣头条的笔试题(此处用Java实现)
求输入一个整数n,整数中2出现的次数(从1到n整数中2出现的次数)

输入 2-12-20-21-22
输出 1-2-3-4-6

import java.util.Scanner;
public class NumberOfBetweenAndN {
	public static void main(String[] args) {
		Scanner in=new Scanner(System.in);
		int num=in.nextInt();
		int temp=NumberOf1Between1AndN_Solution(num);
		System.out.println(temp);
	}
	public static int NumberOf1Between1AndN_Solution(int n) {
	    int count = 0;
	    for(int i=0; i<=n; i++){
	        int temp = i;
	        //如果temp的任意位为2则count++
	        while(temp!=0){
	            if(temp%10 == 2){
	                count++;
	            }
	            temp /= 10;
	        }
	    }
	    return count;
	}

}

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