1 #include <bits/stdc++.h>

 2 //#define loveGsy

 3 #define N 1000005

 4 using namespace std;

 5 int f[N];

 6

 7 int main() {

 8 #ifdef loveGsy

 9     freopen("a.in", "r", stdin);

10     freopen("a.out", "w", stdout);

11 #endif

12     int n, p;

13     cin >> n >> p;

14     f[0] = 1;

15     for (int i = 1; i <= n; i++)

16         for (int j = i; j <= n; j++)

17             f[j] = (f[j-i] + f[j]) % p;

18     cout << f[n] <<endl;

19     return 0;

20 }

 1 #include<bits/stdc++.h>

 2 #define ll long long

 3 using namespace std;

 4 const int N = 1e5 + 10;

 5

 6 int n, p, m; ll ans = 0;

 7 int f[N], g[410][N];

 8

 9 signed main() {

10     cin >> n >> p;

11     m = sqrt(n) + 1;

12     f[0] = 1;

13     for (int i = 1; i < m; i++)

14         for (int j = i; j <= n; j++)

15             f[j] = (f[j] + f[j - i]) % p;

16     g[0][0] = 1;

17     for (int i = 1; i < m; i++)

18         for (int j = i; j <= n; j++) {

19             g[i][j] = g[i][j - i];

20             if (j >= m) g[i][j] = (g[i][j] + g[i - 1][j - m]) % p;

21         }

22     for (int i = 0; i <= n; i++) {

23         int sum = 0;

24         for (int j = 0; j < m; j++) sum = (sum + g[j][n - i]) % p;

25         ans = (ans + 1ll * f[i] * sum) % p;

26     }

27     cout << ans << endl;

28     return 0;

29 }