Submission #1101112

#	Time	Username	Problem	Language	Result	Execution time	Memory
1101112		TgX_2	Tents (JOI18_tents)	C++17	48 / 100	78 ms	71252 KiB

tents

/*-----------------------------
        Author : TgX.2
       11Ti - K28 - CHV
-----------------------------*/

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

#define FOR(i, a, b)       for (int i = (a), _b = (b); i <= _b; i += 1)
#define FORD(i, a, b)      for (int i = (a), _b = (b); i >= _b; i -= 1)

#define fi                 first
#define se                 second
#define len(x)             (int)((x).size())
#define all(x)             (x).begin(), (x).end()

#define _                  << " " <<
#define __                 << "\n"
#define ___                << " "

#define ______________TgX______________ main()
#define int                long long
#define intmax             1e9
#define intmin            -1e9
#define llongmax           1e18
#define llongmin          -1e18
#define memo(a, val)       memset((a), (val), sizeof((a)))

struct custom {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};
template<class T1, class T2> using cmap = unordered_map<T1, T2, custom>;

template<typename T1, typename T2>
bool mini(T1 &a, T2 b)
    {if (a > b) a = b; else return 0; return 1;}

template<typename T1, typename T2>
bool maxi(T1 &a, T2 b)
    {if (a < b) a = b; else return 0; return 1;}
/*-----------------------------*/

const int maxn = 3007;
const int mod  = 1e9 + 7;
int n, m;

int f[maxn][maxn];
int dp(int i, int j) {
    if (i < 0 or j < 0) return 0;
    if (i == 0 or j == 0) return 1;

    int &ans = f[i][j];
    if (ans != -1) return ans;

    ans = 0;
    (ans += dp(i, j - 1)) % mod;
    (ans += ((4 * i) % mod * dp(i - 1, j - 1)) % mod) % mod;
    (ans += (i * (i - 1) / 2 % mod * dp(i - 2, j - 1)) % mod) % mod;
    (ans += ((i * (j - 1)) % mod * dp(i - 1, j - 2)) % mod) % mod;
    return ans;
}

void process() {
    cin >> n >> m;
    memo(f, -1);

    cout << (dp(n, m) - 1 + mod) % mod;

}



/*-----------------------------*/
______________TgX______________ {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen("temp.inp", "r")) {
        freopen("temp.inp", "r", stdin);
        freopen("temp.out", "w", stdout);
    }
    process();
    cerr << "Time: " << 1.0 * clock() / CLOCKS_PER_SEC << " s." __ ;
}


/*==============================+
|INPUT                          |
--------------------------------|

================================+
|OUTPUT                         |
--------------------------------|

===============================*/

Compilation message (stderr)

tents.cpp: In function 'long long int dp(long long int, long long int)':
tents.cpp:66:27: warning: value computed is not used [-Wunused-value]
   66 |     (ans += dp(i, j - 1)) % mod;
      |     ~~~~~~~~~~~~~~~~~~~~~~^~~~~
tents.cpp:67:55: warning: value computed is not used [-Wunused-value]
   67 |     (ans += ((4 * i) % mod * dp(i - 1, j - 1)) % mod) % mod;
      |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
tents.cpp:68:63: warning: value computed is not used [-Wunused-value]
   68 |     (ans += (i * (i - 1) / 2 % mod * dp(i - 2, j - 1)) % mod) % mod;
      |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
tents.cpp:69:61: warning: value computed is not used [-Wunused-value]
   69 |     (ans += ((i * (j - 1)) % mod * dp(i - 1, j - 2)) % mod) % mod;
      |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
tents.cpp: At global scope:
tents.cpp:21:41: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   21 | #define ______________TgX______________ main()
      |                                         ^~~~
tents.cpp:84:1: note: in expansion of macro '______________TgX______________'
   84 | ______________TgX______________ {
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tents.cpp: In function 'int main()':
tents.cpp:88:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |         freopen("temp.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tents.cpp:89:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |         freopen("temp.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 48 / 48
• Subtask 2: 0 / 52