直接运用“两边之和一定大于第三边“即可

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin >> n;
    for(int i = 1; i <= n; i++)
    {
         if(i % 3 == 2 and i % 5 == 3 and i % 7 == 2)
         {
             cout << i << endl; 
         }
    }
}