题解 | #数位五五#

#include <stdio.h>

int count_(int i)
{
    if (i / 10 != 0)
    {
        return ((i % 10) + count_(i / 10));
    }
    return (i % 10);
}//递归计算数位数字之和

int main()
{
    int a, b;
    scanf("%d %d", &a, &b);
    int i = 0;
    int count = 0;
    for (i = a; i <= b; i++)
    {
        if (count_(i) % 5 == 0)
            count++;
    }//循环遍历并计数
    printf("%d\n", count);
    return 0;
}