题解 | 记数问题

#include <stdio.h>

int main() {
    int n, x, temp;
    int i_cnt, x_total_cnt, i;

    scanf("%d %d", &n, &x);

    x_total_cnt = 0;
    for(i = 1; i <= n; i++) {
        i_cnt = 0;
        temp = i;
        while(temp) {
            if(temp % 10 == x) {
                i_cnt++;
            }
            temp = temp / 10;
        }
        x_total_cnt += i_cnt;
    }
        // 64 位输出请用 printf("%lld") to 
    
    printf("%d\n", x_total_cnt);
    
    return 0;
}