This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#warning Check Integer OverFlow
#define ll long long
#define rep(i,a,b) for(int i=a;i<b;i++)
#define per(i,a,b) for(int i=a;i>=b;i--)
#define trav(a,b) for(auto a:b)
#define sz(a) a.size()
#define maxs(a,b) if(b>a)a=b
#define mins(a,b) if(b<a)a=b
#ifdef LOCAL
#define dbg(x) cerr<<"["<<#x<<":"<<x<<"] "
#define dbg2(a,b) dbg(a);dbg(b)
#define dbg3(a,b,c) dbg2(a,b);dbg(c)
#define dln cerr << ln
#else
#define dbg(x) 0
#define dbg2(a,b) 0
#define dbg3(a,b,c) 0
#define dln 0
#endif
#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) (((a)/(__gcd(a,b))) * b)
#define print(arr) for(auto it = arr.begin();it < arr.end();it ++){cout << *it << " ";}cout << ln;
#define all(a) (a).begin(), (a).end()
#define vi vector<int>
#define v vector
#define p pair
#define pii p<int,int>
#define pb push_back
#define mk make_pair
#define f first
#define s second
#define ln "\n"
typedef long double ld;
using namespace std;
using namespace __gnu_pbds;
ll modF=1e9+7;
template<class T> using iset = tree<
T,
null_type,
less<T>,
rb_tree_tag,
tree_order_statistics_node_update>;
/*OUTPUT
*/
v<ll> fac(355,1);
void g(int a,int b,int* x,int* y){
if(a == 0){
*x = 0;
*y = 1;
}
else{
int x1,y1;
g(b % a,a,&x1,&y1);
*x = y1 - (b / a) * x1;
*y = x1;
}
}
ll modInverse(int a){
int x,y;
g(a,modF,&x,&y);
while(x < 0)x += modF;
return x % modF;
}
ll nCr(ll n,ll r){
return (fac[n] * modInverse((fac[n - r] * fac[r]) % modF)) % modF;
}
void solve(){
int n;
cin >> n;
ll dp1[n][n + 1];
ll dp2[n][n + 1];
for(ll i = 0;i < n;i ++){
for(ll j = 0;j <= n;j ++){
if(i == 0){
dp2[i][j] = 1;
if(j == i + 1)
dp1[i][j] = 1;
else
dp1[i][j] = 0;
}
else{
dp1[i][j] = dp2[i][j] = 0;
for(int k = 0;k <= j;k ++){
dp2[i][j] = (dp2[i][j] + (nCr(j,k) * dp2[i - 1][j - k]) % modF) % modF;
}
if(j >= i + 1){
dp1[i][j] = (nCr(j,i + 1) * dp2[i - 1][j - i - 1]) % modF;
}
for(int k = 0;k <= j;k ++){
if(k == i + 1)continue;
dp1[i][j] = (dp1[i][j] + (nCr(j,k) * dp1[i - 1][j - k])) % modF;
}
}
}
}
cout << dp1[n - 1][n] << ln;
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);
int t = 1;
rep(i,1,351){
fac[i] = (fac[i - 1] * i) % modF;
}
// cin >> t;
while(t --){
solve();
}
}
Compilation message (stderr)
zapina.cpp:4:2: warning: #warning Check Integer OverFlow [-Wcpp]
4 | #warning Check Integer OverFlow
| ^~~~~~~
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