题解 | #[NOIP2013]记数问题#

#include<stdio.h>
int main() {
    int n, a;
    //int c[100];
    int i, s;
    int count = 0;
    scanf("%d %d", &n, &a);
    //for(i=1;i<=n;i++)
    //{
    //c[i]=i;
    //}
    for (i = 1; i <= n; i++) {
        s = i;
        if (s < 9) {
            if (s == a)
                count++;
        } else
            while (s) {
                if (s % 10 == a)
                    count++;
                s = s / 10;
            }

    }
    printf("%d", count);
    return 0;
}