题解 | #包含数字9的数#

#include <stdio.h>

int main() {
    int count = 0;//记录个数
    int i = 0;
    for (i = 1; i <= 2019; i++)//遍历
    {
        int m = i;
        while (m > 0)
        {
            if (m % 10 == 9)
            {
                count++;
                break;
            }
            else {
                m /= 10;
            }
        }
    }
    printf("%d\n", count);
    return 0;
}