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| #include<bits/stdc++.h> #define PII pair<int, int> #define LL long long using namespace std; template <class T> inline void read(T &res) { res = 0; bool flag = 0; char c = getchar(); while(c < '0' || '9' < c) {if(c == '-') flag = 1; c = getchar();} while('0' <= c && c <= '9') res = (res << 3) + (res << 1) + (c ^ 48), c = getchar(); if(flag) res = -res; } template <class T, class ...ARC> inline void read(T &res, ARC &...com){ read(res), read(com...); } template <class T> void write(T res) { if(res < 0) putchar('-'), res = -res; if(res > 9) write(res / 10); putchar(res % 10 + '0'); } template <> inline void write(char c) { putchar(c); } template <> inline void write(char *s) { while(*s) putchar(*s ++);} template <class T, class ...ARC> inline void write(T res, ARC ...com) { write(res), write(com...); } const int N = 1e6 + 5; int n, mod; int f[N << 1]; int fac[N], inv[N]; inline void init(int x) { fac[0] = inv[0] = inv[1] = 1; for(int i = 1;i <= x;i ++) fac[i] = 1ll * fac[i - 1] * i % mod; for(int i = 2;i <= x;i ++) inv[i] = 1ll * (mod - mod / i) * inv[mod % i] % mod; for(int i = 2;i <= x;i ++) inv[i] = 1ll * inv[i] * inv[i - 1] % mod; } inline int C(int x, int y) { if(x < y || y < 0) return 0; if(x <= mod && y <= mod) return 1ll * fac[x] * inv[y] % mod * inv[x - y] % mod; return 1ll * C(x / mod, y / mod) * C(x % mod, y % mod) % mod; } inline int get_l(int x) { int l = 1; while(l * 2 <= x) l <<= 1;
} int sz[N << 1]; void dfs(int x) { if(x > n) return f[x] = 1, void(); dfs(x << 1), dfs(x << 1 | 1); sz[x] += sz[x << 1] + sz[x << 1 | 1] + 1; f[x] = 1ll * C(sz[x] - 1, sz[x << 1]) * f[x << 1] % mod * f[x << 1 | 1] % mod; } int main() { read(n, mod); init(min(n, mod)); dfs(1); write(f[1]); return 0; }
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