oj.uz

Submission #421717

# Submission time Handle Problem Language Result Execution time Memory
421717 2021-06-09T11:15:07 Z amunduzbaev Tents (JOI18_tents) C++14
100 / 100
 373 ms 71216 KB 
/* made by amunduzbaev */
 
//~ #include <ext/pb_ds/assoc_container.hpp>
//~ #include <ext/pb_ds/tree_policy.hpp>
#include "bits/stdc++.h"
 
using namespace std;
//~ using namespace __gnu_pbds;

#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define NeedForSpeed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vv vector
#define mem(arr, v) memset(arr, v, sizeof arr)
#define int long long
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef vector<int> vii;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) { return a > b ? a = b, true : false; }
template<class T> bool umax(T& a, const T& b) { return a < b ? a = b, true : false; }
template<int sz> using tut = array<int, sz>;
void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);  
	freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
//~ template<class T> using oset = tree<T, 
//~ null_type, less_equal<T>, rb_tree_tag, 
//~ tree_order_statistics_node_update> ordered_set;
 
const int N = 3e3+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
 
#define MULTI 0
int n, m, k, s, t, q, ans, res, a[N];
int dp[N][N];

int rec(int i, int E){
	if(i > n){
		if(E == m) return 0;
		return 1;
	}
	int& res = dp[i][E];
	if(~res) return res;
	res = rec(i+1, E);
	if(E) res = (res + rec(i+1, E-1) * E * 4) % mod;
	if(E && i+1 <= n) res = (res + rec(i+2, E-1) * E * (n-i)) % mod;
	if(E > 1) res = (res + rec(i+1, E - 2) * E *(E - 1) / 2) % mod;
	return res;
}

void solve(int t_case){
	mem(dp, -1);
	cin>>n>>m;
	cout<<rec(1, m)<<"\n";
}

signed main(){
	NeedForSpeed
	if(MULTI){
		int t; cin>>t;
		for(int t_case = 1; t_case <= t; t_case++) solve(t_case);
	} else solve(1);
	return 0;
}

Compilation message

tents.cpp: In function 'void usaco(std::string)':
tents.cpp:32:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 | void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tents.cpp:33:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |  freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 70876 KB Output is correct
2 Correct 31 ms 70876 KB Output is correct
3 Correct 31 ms 70988 KB Output is correct
4 Correct 30 ms 70988 KB Output is correct
5 Correct 30 ms 70920 KB Output is correct
6 Correct 33 ms 70996 KB Output is correct
7 Correct 32 ms 70988 KB Output is correct
8 Correct 32 ms 70984 KB Output is correct
9 Correct 31 ms 70928 KB Output is correct
10 Correct 31 ms 71008 KB Output is correct
11 Correct 36 ms 70880 KB Output is correct
12 Correct 34 ms 70980 KB Output is correct

Subtask #2
52.0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 70876 KB Output is correct
2 Correct 31 ms 70876 KB Output is correct
3 Correct 31 ms 70988 KB Output is correct
4 Correct 30 ms 70988 KB Output is correct
5 Correct 30 ms 70920 KB Output is correct
6 Correct 33 ms 70996 KB Output is correct
7 Correct 32 ms 70988 KB Output is correct
8 Correct 32 ms 70984 KB Output is correct
9 Correct 31 ms 70928 KB Output is correct
10 Correct 31 ms 71008 KB Output is correct
11 Correct 36 ms 70880 KB Output is correct
12 Correct 34 ms 70980 KB Output is correct
13 Correct 30 ms 70956 KB Output is correct
14 Correct 31 ms 71064 KB Output is correct
15 Correct 253 ms 71196 KB Output is correct
16 Correct 37 ms 70996 KB Output is correct
17 Correct 53 ms 70976 KB Output is correct
18 Correct 78 ms 71028 KB Output is correct
19 Correct 303 ms 71128 KB Output is correct
20 Correct 241 ms 71108 KB Output is correct
21 Correct 150 ms 71016 KB Output is correct
22 Correct 165 ms 71144 KB Output is correct
23 Correct 117 ms 71192 KB Output is correct
24 Correct 373 ms 71216 KB Output is correct
25 Correct 286 ms 71184 KB Output is correct
26 Correct 337 ms 71200 KB Output is correct
27 Correct 347 ms 71212 KB Output is correct