题解 | #整数中1出现的次数（从1到n中1出现的次数）#

class Solution {
  public:
    int NumberOf1Between1AndN_Solution(int n) {
        if (n == 0) {
            return 0;
        }
        if (n < 10) {
            return 1;
        }
        int count = 1;
        for (int i = 10; i <= n; ++i) {
            int temp = i;
            while (temp > 0) {
                if (temp % 10 == 1) {
                    count++;
                }
                temp /= 10;
            }
        }
        return count;
    }
};