Submission #456324

# Submission time Handle Problem Language Result Execution time Memory
456324 2021-08-06T12:15:06 Z ACmachine Tents (JOI18_tents) C++17
100 / 100
268 ms 71476 KB
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T, typename U> using ordered_map = tree<T, U, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

typedef long long ll;
typedef long double ld;

typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

typedef vector<int> vi;
typedef vector<ll> vll;

#define FOR(i,j,k,in) for(int i=(j); i < (k);i+=in)
#define FORD(i,j,k,in) for(int i=(j); i >=(k);i-=in)
#define REP(i,b) FOR(i,0,b,1)
#define REPD(i,b) FORD(i,b,0,1)
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define all(x) begin(x), end(x)
#define MANY_TESTS int tcase; cin >> tcase; while(tcase--)

const double EPS = 1e-9;

const ll INFF = 1e18;
const int INF = 1e9;
const ld PI = acos((ld)-1);
const vi dy = {1, 0, -1, 0, -1, 1, 1, -1};
const vi dx = {0, 1, 0, -1, -1, 1, -1, 1};

void DBG(){cout << "]" << endl;}
template<typename T, typename ...U> void DBG(const T& head, const U... args){ cout << head << "; "; DBG(args...); }
#define dbg(...) cout << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__);
#define chk() cout << "Check at line(" << __LINE__ << ") hit." << endl;

template<class T, unsigned int U>
ostream& operator<<(ostream& out, const array<T, U> &v){out << "[";  REP(i, U) out << v[i] << ", ";  out << "]"; return out;}
template <class T, class U>
ostream& operator<<(ostream& out, const pair<T, U> &par) {out << "[" << par.first << ";" << par.second << "]"; return out;}
template <class T>
ostream& operator<<(ostream& out, const set<T> &cont) { out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template <class T, class U>
ostream& operator<<(ostream& out, const map<T, U> &cont) {out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template<class T>
ostream& operator<<(ostream& out, const vector<T> &v){ out << "[";  REP(i, v.size()) out << v[i] << ", ";  out << "]"; return out;}

template<class T>
istream& operator>>(istream& in, vector<T> &v){ for(auto &x : v) in >> x; return in; }

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());




const int mod = (int)1e9+7;
struct Mint{
    int val;
    Mint(){ val = 0; }
    Mint(long long v){
        val = (-mod <= v && v < mod) ? v : v%mod;
        if(val < 0) val+= mod;
    }
    // operators
    Mint operator-(){return Mint(-val);}
    Mint& operator+=(const Mint& other){ val+=other.val; if(val >= mod) val-=mod; return *this;}
    Mint& operator-=(const Mint& other){ val-=other.val; if(val < 0) val+=mod; return *this;}
    Mint& operator*=(const Mint& other){ val=((long long)val*other.val)%mod; return *this;}
    friend Mint binpow(Mint a, long long p){
        Mint res(1);
        while(p > 0){
            if(p&1) res*=a; a*=a; p>>=1;
        }
        return res;
    }
    friend Mint inv(Mint a){ return binpow(a, mod-2); }
    Mint& operator/=(const Mint &other){ return (*this)*=inv(other);}

    friend Mint operator+(Mint a, const Mint& b){ return a+=b; }
    friend Mint operator-(Mint a, const Mint& b){ return a-=b; }
    friend Mint operator*(Mint a, const Mint& b){ return a*=b; }
    friend Mint operator/(Mint a, const Mint& b){ return a/=b; }

    bool operator==(const Mint &other){return val == other.val;}
    bool operator!=(const Mint &other){return val != other.val;}
    bool operator<(const Mint &other){return val < other.val;}
    // io
    friend ostream& operator<<(ostream &out, Mint &a){ return out << a.val; }
};
int main(){
 	ios_base::sync_with_stdio(false);
 	cin.tie(NULL); cout.tie(NULL);
 	const int mx = 3020;
    vector<vector<Mint>> ncr(mx, vector<Mint>(mx));
    ncr[0][0] = Mint(1);
    FOR(i, 1, mx, 1){
        ncr[i][0] = ncr[i][i] = Mint(1);
        FOR(j, 1, i, 1){
            ncr[i][j] = (ncr[i - 1][j - 1] + ncr[i - 1][j]);
        }
    }
    int h, w;
    cin >> h >> w;
    vector<vector<Mint>> dp(w + 1, vector<Mint>(h + 1, Mint(0)));
    FOR(i, 0, h + 1, 1){
        dp[0][i] = Mint(1);
    }
    FOR(i, 0, w + 1, 1){
        dp[i][0] = Mint(1);
    }
    FOR(i, 1, w + 1, 1){
        FOR(j, 1, h + 1, 1){
            dp[i][j] += dp[i - 1][j];
            dp[i][j] += Mint(4) * Mint(j) * dp[i - 1][j - 1];
            if(j > 1)
                dp[i][j] += ncr[j][2] * dp[i - 1][j - 2];
            if(i > 1)
                dp[i][j] += Mint(j) * Mint(i - 1) * dp[i - 2][j - 1];
        }
    }
    dp[w][h] -= Mint(1);
    cout << dp[w][h] << "\n";
    return 0;
}

Compilation message

tents.cpp: In function 'Mint binpow(Mint, long long int)':
tents.cpp:78:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   78 |             if(p&1) res*=a; a*=a; p>>=1;
      |             ^~
tents.cpp:78:29: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   78 |             if(p&1) res*=a; a*=a; p>>=1;
      |                             ^
# Verdict Execution time Memory Grader output
1 Correct 26 ms 36108 KB Output is correct
2 Correct 31 ms 36028 KB Output is correct
3 Correct 26 ms 36060 KB Output is correct
4 Correct 26 ms 36032 KB Output is correct
5 Correct 25 ms 36160 KB Output is correct
6 Correct 26 ms 36172 KB Output is correct
7 Correct 27 ms 36128 KB Output is correct
8 Correct 27 ms 36172 KB Output is correct
9 Correct 26 ms 36088 KB Output is correct
10 Correct 26 ms 36248 KB Output is correct
11 Correct 24 ms 36044 KB Output is correct
12 Correct 27 ms 36472 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 26 ms 36108 KB Output is correct
2 Correct 31 ms 36028 KB Output is correct
3 Correct 26 ms 36060 KB Output is correct
4 Correct 26 ms 36032 KB Output is correct
5 Correct 25 ms 36160 KB Output is correct
6 Correct 26 ms 36172 KB Output is correct
7 Correct 27 ms 36128 KB Output is correct
8 Correct 27 ms 36172 KB Output is correct
9 Correct 26 ms 36088 KB Output is correct
10 Correct 26 ms 36248 KB Output is correct
11 Correct 24 ms 36044 KB Output is correct
12 Correct 27 ms 36472 KB Output is correct
13 Correct 25 ms 36180 KB Output is correct
14 Correct 26 ms 36144 KB Output is correct
15 Correct 188 ms 58084 KB Output is correct
16 Correct 34 ms 37596 KB Output is correct
17 Correct 50 ms 41028 KB Output is correct
18 Correct 60 ms 42228 KB Output is correct
19 Correct 203 ms 61732 KB Output is correct
20 Correct 164 ms 56608 KB Output is correct
21 Correct 107 ms 49640 KB Output is correct
22 Correct 117 ms 49308 KB Output is correct
23 Correct 76 ms 43484 KB Output is correct
24 Correct 268 ms 71476 KB Output is correct
25 Correct 200 ms 62356 KB Output is correct
26 Correct 233 ms 66208 KB Output is correct
27 Correct 267 ms 70100 KB Output is correct