题解 | #数位五五#

#include <stdio.h>

int UnitSum(int x)
{
    int sum = 0;
    while(x)
    {
        sum += x % 10;
        x /= 10;
    }

    return sum;
}

int main() {
    int start = 0;
    int end = 0;
    int sum = 0;
    while (scanf("%d %d", &start,&end) != EOF) 
    { 
        for (int i = start; i <= end; i++)
        {
            if (UnitSum(i) % 5 == 0)
            {
                sum++;
            }
        }
    }

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