[Word] insert automatic directory

Before automatically generated table of contents, first set the outline level based on heading styles.
1, place the cursor on the directory you want to insert references -> directory small triangle button -> drop-down menu to select automatic directory 1

2, automatic generation of hierarchical directory click
3, after modifying the relevant headings, select the directory, click on the upper left cornerUpdates

Contents can be updated in real time!

#include<iostream>
using namespace std;
int s1,s2,s3;
bool flag = 1;
int main()
{
    freopen("1.txt","r",stdin);
    freopen("2.txt","w",stdout);
    int k;cin >> k;
    for(int i = 10000;i <= 30000;i++)
    {
        s1 = i / 100;
        s3 = i % 1000;
        s2 = (i/10)%1000;
        if(s1%k==0&&s2%k==0&&s3%k==0)
            {
                cout << i <<endl;
                flag = 0;
            }
    }
    if(flag)
        cout << "NO" ;//实在没想到是因为No打成了NO，太粗心了
}