L1-008 求整数段和 分数 10

考察格式 printf("%5d",i);

// 5'43"
#include <iostream>
using namespace std;
int main()
{
    int a, b;
    cin >> a >> b;
    int sum = 0;
    int cnt = 1;
    for(int i = a; i <= b; ++ i, ++ cnt)
    {
        printf("%5d",i);
        sum += i;
        if(cnt % 5 == 0 && i != a || i == b) cout << endl;
	}
    cout << "Sum = " << sum;
    return 0;
}