ZZNU 正约数之和

    #include <iostream>
    using namespace std;
     
    int main() {
        int T, n;
        cin >> T;
        while(T--) {
          cin >> n;
          long long ans = 0;
          for(int i=1; i<=n; i++) {
              ans += n/i*i;
          }
          cout << ans << endl;
        }
        return 0;
    }

# include <stdio.h>
# include <string.h>


int a[1300001];


int main(void)
{
    int i, j;
            //把每个数的约数存在数组里。
    for (i = 1; i <= 7000000; i ++)
    {
        for (j = i; j <= 1300000; j = j+i)
        {
            a[j] += i;
        }
    }
    int t, n;
    long long sum;
    scanf("%d", &t);
    while (t --)
    {
        sum = 0;
        scanf("%d", &n);
        for (i = 1; i <= n; i ++)
            sum += a[i];
        printf("%lld\n", sum);
    }
    return 0;
}