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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#321162#8211. Enumerating Substringsucup-team008#AC ✓1418ms18996kbC++178.5kb2024-02-04 05:43:142024-02-04 05:43:14

Judging History

你现在查看的是最新测评结果

  • [2024-02-04 05:43:14]
  • 评测
  • 测评结果:AC
  • 用时:1418ms
  • 内存:18996kb
  • [2024-02-04 05:43:14]
  • 提交

answer

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <unordered_set>
#include <vector>

using namespace std;

// BEGIN NO SAD
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define trav(a, x) for(auto& a : x)
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
typedef vector<int> vi;
#define f first
#define s second
#define derr if(1) cerr

void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
 
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#define debug(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << flush;
// END NO SAD

template<class Fun>
class y_combinator_result {
  Fun fun_;
public:
  template<class T>
  explicit y_combinator_result(T &&fun): fun_(std::forward<T>(fun)) {}

  template<class ...Args>
  decltype(auto) operator()(Args &&...args) {
    return fun_(std::ref(*this), std::forward<Args>(args)...);
  }
};

template<class Fun>
decltype(auto) y_combinator(Fun &&fun) {
  return y_combinator_result<std::decay_t<Fun>>(std::forward<Fun>(fun));
}

template<class T>
bool updmin(T& a, T b) {
  if(b < a) {
    a = b;
    return true;
  }
  return false;
}
template<class T>
bool updmax(T& a, T b) {
  if(b > a) {
    a = b;
    return true;
  }
  return false;
}
typedef int64_t ll;

struct barrett_reduction {
    unsigned mod;
    uint64_t div;
 
    barrett_reduction(unsigned m) : mod(m), div(-1LLU / m) {}
 
    unsigned operator()(uint64_t a) const {
#ifdef __SIZEOF_INT128__
        uint64_t q = uint64_t(__uint128_t(div) * a >> 64);
        uint64_t r = a - q * mod;
        return unsigned(r < mod ? r : r - mod);
#endif
        return unsigned(a % mod);
    }
};
 
template<const int &MOD, const barrett_reduction &barrett>
struct _b_int {
    int val;
 
    _b_int(int64_t v = 0) {
        if (v < 0) v = v % MOD + MOD;
        if (v >= MOD) v %= MOD;
        val = int(v);
    }
 
    _b_int(uint64_t v) {
        if (v >= uint64_t(MOD)) v %= MOD;
        val = int(v);
    }
 
    _b_int(int v) : _b_int(int64_t(v)) {}
    _b_int(unsigned v) : _b_int(uint64_t(v)) {}
 
    static int inv_mod(int a, int m = MOD) {
        // https://en.wikipedia.org/wiki/Extended_Euclidean_algorithm#Example
        int g = m, r = a, x = 0, y = 1;
 
        while (r != 0) {
            int q = g / r;
            g %= r; swap(g, r);
            x -= q * y; swap(x, y);
        }
 
        return x < 0 ? x + m : x;
    }
 
    explicit operator int() const { return val; }
    explicit operator unsigned() const { return val; }
    explicit operator int64_t() const { return val; }
    explicit operator uint64_t() const { return val; }
    explicit operator double() const { return val; }
    explicit operator long double() const { return val; }
 
    _b_int& operator+=(const _b_int &other) {
        val -= MOD - other.val;
        if (val < 0) val += MOD;
        return *this;
    }
 
    _b_int& operator-=(const _b_int &other) {
        val -= other.val;
        if (val < 0) val += MOD;
        return *this;
    }
 
    static unsigned fast_mod(uint64_t x) {
#if !defined(_WIN32) || defined(_WIN64)
        return barrett(x);
#endif
        // Optimized mod for Codeforces 32-bit machines.
        // x must be less than 2^32 * MOD for this to work, so that x / MOD fits in an unsigned 32-bit int.
        unsigned x_high = unsigned(x >> 32), x_low = unsigned(x);
        unsigned quot, rem;
        asm("divl %4\n"
            : "=a" (quot), "=d" (rem)
            : "d" (x_high), "a" (x_low), "r" (MOD));
        return rem;
    }
 
    _b_int& operator*=(const _b_int &other) {
        val = fast_mod(uint64_t(val) * other.val);
        return *this;
    }
 
    _b_int& operator/=(const _b_int &other) {
        return *this *= other.inv();
    }
 
    friend _b_int operator+(const _b_int &a, const _b_int &b) { return _b_int(a) += b; }
    friend _b_int operator-(const _b_int &a, const _b_int &b) { return _b_int(a) -= b; }
    friend _b_int operator*(const _b_int &a, const _b_int &b) { return _b_int(a) *= b; }
    friend _b_int operator/(const _b_int &a, const _b_int &b) { return _b_int(a) /= b; }
 
    _b_int& operator++() {
        val = val == MOD - 1 ? 0 : val + 1;
        return *this;
    }
 
    _b_int& operator--() {
        val = val == 0 ? MOD - 1 : val - 1;
        return *this;
    }
 
    _b_int operator++(int) { _b_int before = *this; ++*this; return before; }
    _b_int operator--(int) { _b_int before = *this; --*this; return before; }
 
    _b_int operator-() const {
        return val == 0 ? 0 : MOD - val;
    }
 
    friend bool operator==(const _b_int &a, const _b_int &b) { return a.val == b.val; }
    friend bool operator!=(const _b_int &a, const _b_int &b) { return a.val != b.val; }
    friend bool operator<(const _b_int &a, const _b_int &b) { return a.val < b.val; }
    friend bool operator>(const _b_int &a, const _b_int &b) { return a.val > b.val; }
    friend bool operator<=(const _b_int &a, const _b_int &b) { return a.val <= b.val; }
    friend bool operator>=(const _b_int &a, const _b_int &b) { return a.val >= b.val; }
 
    _b_int inv() const {
        return inv_mod(val);
    }
 
    _b_int pow(int64_t p) const {
        if (p < 0)
            return inv().pow(-p);
 
        _b_int a = *this, result = 1;
 
        while (p > 0) {
            if (p & 1)
                result *= a;
 
            p >>= 1;
 
            if (p > 0)
                a *= a;
        }
 
        return result;
    }
 
    friend ostream& operator<<(ostream &os, const _b_int &m) {
        return os << m.val;
    }
 
    friend istream& operator>>(istream &is, _b_int &m) {
        int64_t x;
        is >> x;
        m = x;
        return is;
    }
};
 
int MOD = int(1e9) + 7;
barrett_reduction barrett(MOD);
using mnum = _b_int<MOD, barrett>;

void solve() {
  int n, m, k;
  cin >> n >> m >> k;
  vector<vector<mnum>> wordcnt(m+1);
  for(int i = 0; i <= m; i++) wordcnt[i].resize(m+1);
  wordcnt[0][0] = 1;
  for(int i = 0; i < m; i++) {
    for(int j = 0; j <= i; j++) {
      int once = 2*j-i;
      int zero = k-j;
      if(zero > 0) wordcnt[i+1][j+1] += wordcnt[i][j] * zero;
      if(once > 0) wordcnt[i+1][j] += wordcnt[i][j] * once;
    }
  }
  mnum ret = 0;
  mnum total = 0;
  for(int i = 0; i <= m; i++) {
    mnum scale = wordcnt[m][i];
    total += scale;
  }
  for(int innerlen = 0; innerlen < m; innerlen++) {
    if(m%2 != innerlen%2) continue;
    int blen = (m-innerlen)/2;
    mnum distinctwords = 0;
    for(int d = 0; d <= innerlen; d++) {
      mnum curr = wordcnt[innerlen][d];
      for(int i = 0; i < blen; i++) curr *= (k-d-i);
      distinctwords += curr;
    }
    total -= distinctwords;
    mnum inner = 0;
    for(int a = 1; true; a++) {
      int candlen = (a+1) * blen + a * innerlen;
      if(candlen > n) break;
      mnum scale = (n-candlen+1) * mnum(k).pow(n-candlen);
      if(a%2) inner += scale;
      else inner -= scale;
    }
    ret += inner * distinctwords;
  }
  // no border
  mnum scale = (n-m+1) * mnum(k).pow(n-m);
  scale *= total;
  ret += scale;
  cout << ret << "\n";
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  solve();
}

这程序好像有点Bug,我给组数据试试?

詳細信息

Test #1:

score: 100
Accepted
time: 1ms
memory: 3740kb

input:

4 2 3

output:

228

result:

ok 1 number(s): "228"

Test #2:

score: 0
Accepted
time: 1418ms
memory: 18996kb

input:

999999 1999 12345678

output:

52352722

result:

ok 1 number(s): "52352722"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3600kb

input:

7 4 2

output:

182

result:

ok 1 number(s): "182"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3612kb

input:

4 3 4

output:

480

result:

ok 1 number(s): "480"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3616kb

input:

3 1 1

output:

3

result:

ok 1 number(s): "3"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3744kb

input:

5 5 1

output:

0

result:

ok 1 number(s): "0"

Test #7:

score: 0
Accepted
time: 1ms
memory: 3548kb

input:

7 4 3

output:

5784

result:

ok 1 number(s): "5784"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3532kb

input:

5 2 4

output:

3932

result:

ok 1 number(s): "3932"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3816kb

input:

8 2 2

output:

1522

result:

ok 1 number(s): "1522"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3528kb

input:

8 1 2

output:

2048

result:

ok 1 number(s): "2048"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3600kb

input:

7 5 3

output:

2430

result:

ok 1 number(s): "2430"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3536kb

input:

10 4 3

output:

272004

result:

ok 1 number(s): "272004"

Test #13:

score: 0
Accepted
time: 91ms
memory: 4648kb

input:

675978 614 2

output:

0

result:

ok 1 number(s): "0"

Test #14:

score: 0
Accepted
time: 14ms
memory: 3532kb

input:

244613 38 1

output:

0

result:

ok 1 number(s): "0"

Test #15:

score: 0
Accepted
time: 575ms
memory: 11584kb

input:

186293 1462 1

output:

0

result:

ok 1 number(s): "0"

Test #16:

score: 0
Accepted
time: 127ms
memory: 6248kb

input:

24867 886 1

output:

0

result:

ok 1 number(s): "0"

Test #17:

score: 0
Accepted
time: 249ms
memory: 7312kb

input:

976164 1014 2

output:

0

result:

ok 1 number(s): "0"

Test #18:

score: 0
Accepted
time: 14ms
memory: 3548kb

input:

179356 2 716844809

output:

577866092

result:

ok 1 number(s): "577866092"

Test #19:

score: 0
Accepted
time: 38ms
memory: 3600kb

input:

621001 130 310625363

output:

892869197

result:

ok 1 number(s): "892869197"

Test #20:

score: 0
Accepted
time: 147ms
memory: 6000kb

input:

678862 850 754662812

output:

582264789

result:

ok 1 number(s): "582264789"

Test #21:

score: 0
Accepted
time: 200ms
memory: 7048kb

input:

650845 978 348443366

output:

825425732

result:

ok 1 number(s): "825425732"

Test #22:

score: 0
Accepted
time: 52ms
memory: 3932kb

input:

669914 402 87448112

output:

318098088

result:

ok 1 number(s): "318098088"

Test #23:

score: 0
Accepted
time: 88ms
memory: 4080kb

input:

998593 530 681228665

output:

408255654

result:

ok 1 number(s): "408255654"

Test #24:

score: 0
Accepted
time: 1287ms
memory: 18128kb

input:

369361 1954 125266115

output:

509912384

result:

ok 1 number(s): "509912384"

Test #25:

score: 0
Accepted
time: 498ms
memory: 10736kb

input:

900226 1378 424079373

output:

406320917

result:

ok 1 number(s): "406320917"

Test #26:

score: 0
Accepted
time: 593ms
memory: 12016kb

input:

334887 1506 17859926

output:

503264679

result:

ok 1 number(s): "503264679"

Test #27:

score: 0
Accepted
time: 89ms
memory: 4416kb

input:

936048 544 53978328

output:

548647866

result:

ok 1 number(s): "548647866"

Test #28:

score: 0
Accepted
time: 352ms
memory: 9356kb

input:

152789 1264 792983073

output:

839541707

result:

ok 1 number(s): "839541707"

Test #29:

score: 0
Accepted
time: 499ms
memory: 10688kb

input:

714493 1392 91796331

output:

721071046

result:

ok 1 number(s): "721071046"

Test #30:

score: 0
Accepted
time: 105ms
memory: 5680kb

input:

269571 816 830801077

output:

330064211

result:

ok 1 number(s): "330064211"

Test #31:

score: 0
Accepted
time: 196ms
memory: 6732kb

input:

845120 944 424581630

output:

348960190

result:

ok 1 number(s): "348960190"

Test #32:

score: 0
Accepted
time: 41ms
memory: 3932kb

input:

533990 368 163586376

output:

522092095

result:

ok 1 number(s): "522092095"

Test #33:

score: 0
Accepted
time: 989ms
memory: 15696kb

input:

181707 1792 462399634

output:

373795106

result:

ok 1 number(s): "373795106"

Test #34:

score: 0
Accepted
time: 1221ms
memory: 17616kb

input:

417349 1920 761212891

output:

587051329

result:

ok 1 number(s): "587051329"

Test #35:

score: 0
Accepted
time: 442ms
memory: 10280kb

input:

526583 1344 500217637

output:

108767800

result:

ok 1 number(s): "108767800"

Test #36:

score: 0
Accepted
time: 129ms
memory: 5464kb

input:

867054 769 93998191

output:

239123369

result:

ok 1 number(s): "239123369"

Extra Test:

score: 0
Extra Test Passed