제출 #1197025

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1197025		sitingfake	Kangaroo (CEOI16_kangaroo)	C++20	100 / 100	30 ms	23112 KiB

kangaroo

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

// define

#define execute cerr << " Time: " << fixed << setprecision(6) << (1.0 * clock() / CLOCKS_PER_SEC) << "s\n";
#define ll long long
#define ld double
#define ii pair<int,int>
#define se second
#define fi first
#define iii pair<int,ii>
#define all(v) v.begin(),v.end()
#define bit(x,i) (((x)>>(i))&1LL)
#define flip(x,i) ((x)^(1LL<<(i)))
#define ms(d,x) memset(d,x,sizeof(d))
#define sitingfake 1
#define orz 1

//constant

const ll mod = 1e9 + 7;
const long long linf = 4557430888798830399;
const int inf = 1061109567;
const int maxarr = 1e6 + 5;
const int dx[] = {0 , 1 , -1 , 0};
const int dy[] = {1 , 0 , 0 , -1};

template<typename T> bool maximize(T &a, const T &b)
{
    if(a < b) {a = b; return 1;}
    return 0;
}

template<typename T> bool minimize(T &a, const T &b)
{
    if(a > b) {a = b; return 1;}
    return 0;
}

inline void Plus(ll & a ,ll b)
{
    b %= mod;
    a += b;
    if(a >= mod) a -= mod;
    if(a < 0) a += mod;
    return;
}

inline void Mul(ll & a, ll b)
{
    a %= mod; b %= mod;
    a *= b;
    a %= mod;
    return;
}

//code

const int maxn = 2e3 + 7;

int n , s , t;

ll dp[maxn][maxn];


void solve(void)
{
    cin >> n >> s >> t;

    dp[0][0] = 1;

    for(int i = 1; i <= n ;i++)
    {
        for(int j = 1; j <= i ; j++)
        {
            if(i == s || i == t)
            {
                Plus(dp[i][j] , dp[i-1][j]);
                Plus(dp[i][j] , dp[i-1][j-1]);
            }
            else
            {
                Plus(dp[i][j] , dp[i-1][j+1] *(1ll * j));

                Plus(dp[i][j] , dp[i-1][j-1] * 1ll * (j - (i > s) - (i > t)));
            }
        }
    }

    cout << dp[n][1];
}
/**
**/
signed main()
{
   ios_base::sync_with_stdio(0);
   cin.tie(0);
   cout.tie(0);

   #define task ""

   if(fopen(task".inp","r"))
   {
       freopen(task".inp","r",stdin);
       freopen(task".out","w",stdout);
   }

   int tc; tc = 1;

   while(tc--) solve();

   //execute;
}

컴파일 시 표준 에러 (stderr) 메시지

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:105:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  105 |        freopen(task".inp","r",stdin);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
kangaroo.cpp:106:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  106 |        freopen(task".out","w",stdout);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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