Submission #1252014

#	Time	Username	Problem	Language	Result	Execution time	Memory
1252014		_rain_	Kangaroo (CEOI16_kangaroo)	C++20	6 / 100	0 ms	328 KiB

kangaroo

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;

#define FOR(i,a,b) for(int i = (a) , _b = (b); i <= _b; ++i)
#define MASK(x) ((LL)(1)<<(x))
#define BIT(mask , x) (((mask)>>(x))&(1))

template<class X , class Y>
	bool maximize(X &x , Y y){
		if (x<y) return x=y,true; else return false;
	}
template<class X,class Y>
	bool minimize(X &x, Y y){
		if (x>y) return x=y,true; else return false;
	}
template<class T>
	void compress(vector<T>&data){
		sort(data.begin() , data.end()) ; 
		data.resize(unique(data.begin() , data.end()) - data.begin());
		return;
	}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
	int Rand(int l,int r){
		return uniform_int_distribution<int>(l,r)(rng);
	}

const int N = (int)2000;
const int MOD = (int)1e9+7;
	int add(int a,int b){
		return a + b >= MOD ?a + b - MOD : a + b;
	}
	int start , finish , n;

namespace subtask1{
	int type(int prev,int cur){
		if (prev < cur) return 1;
		return 0;
	}
	
	const int MAXN = 8;
	int dp[MASK(MAXN)][MAXN][MAXN];
	
	void main_code(void){
		--start  , --finish;
		FOR(i,0,n-1) if (i!=start) dp[MASK(i)|MASK(start)][start][i] = 1;
		FOR(mask,0,MASK(n)-1) FOR(i,0,n){
				if (BIT(mask,i)) {
					FOR(j,0,n) if (i!=j){
						FOR(nxt , 0 , n) if (!BIT(mask,nxt)){
							if (type(nxt , i) == type(j , i)) dp[mask|MASK(nxt)][i][nxt] = add(dp[mask|MASK(nxt)][i][nxt] , dp[mask][j][i]);	
						}
					}
				} 
			}
		int ans = 0;
		FOR(i,0,n-1) if (i != finish) ans = add(ans , dp[MASK(n)-1][i][finish]);
		cout<<ans;
	}
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0) ; cout.tie(0);
	#define name "main"
		if (fopen(name".inp","r")){
			freopen(name".inp","r",stdin);
			freopen(name".out","w",stdout);
		}
	
		cin >> n >> start >> finish;
		if (n <= 8) return subtask1::main_code() , 0;	
}

Compilation message (stderr)

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:67:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |                         freopen(name".inp","r",stdin);
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
kangaroo.cpp:68:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   68 |                         freopen(name".out","w",stdout);
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 0 / 30
• Subtask 3: 0 / 15
• Subtask 4: 0 / 49