oj.uz

Submission #438745

# Submission time Handle Problem Language Result Execution time Memory
438745 2021-06-28T14:34:48 Z SorahISA Anagramistica (COCI21_anagramistica) C++17
110 / 110
 21 ms 24496 KB 
// #pragma GCC optimize("Ofast", "unroll-loops")
#include <bits/stdc++.h>
using namespace std;

#define int long long
#define double long double
using pii = pair<int, int>;
template<typename T>
using Prior = std::priority_queue<T>;
template<typename T>
using prior = std::priority_queue<T, vector<T>, greater<T>>;

#define X first
#define Y second
#define eb emplace_back
#define ALL(x) begin(x), end(x)
#define RALL(x) rbegin(x), rend(x)
#define fastIO() ios_base::sync_with_stdio(0), cin.tie(0)

template<class T>
ostream& operator << (ostream &os, vector<T> vec) {
    for (int i = 0; i < vec.size(); ++i) {
        if (i) os << " ";
        os << vec[i];
    }
    return os;
}

const int maxn = 2000 + 5;
const int mod = 1E9 + 7;

map<string, int> cnt;
int cnm[maxn][maxn];

void init() {
    for (int i = 0; i < maxn; ++i) cnm[i][0] = cnm[i][i] = 1;
    for (int i = 2; i < maxn; ++i) {
        for (int j = 1; j < i; ++j) cnm[i][j] = (cnm[i-1][j-1] + cnm[i-1][j]) % mod;
    }
}

void solve() {
    int n, k; cin >> n >> k;
    
    for (int i = 0; i < n; ++i) {
        string s; cin >> s;
        sort(ALL(s)), ++cnt[s];
    }
    
    vector<int> nums;
    for (auto [str, app] : cnt) nums.eb(app);
    sort(ALL(nums)); /// useless
    
    // cout << nums << "\n";
    
    int dp[nums.size()+1][k+1];
    memset(dp, 0x00, sizeof(dp)); dp[0][0] = 1;
    /// dp[i][j]: use i stacks to form j pairs ///
    for (int i = 1; i <= nums.size(); ++i) {
        for (int l = 0; l <= nums[i-1]; ++l) {
            for (int j = cnm[l][2]; j <= k; ++j) {
                dp[i][j] = (dp[i][j] + dp[i-1][j-cnm[l][2]] * cnm[nums[i-1]][l]) % mod;
            }
        }
    }
    cout << dp[nums.size()][k] << "\n";
    
    // for (int i = 0; i <= nums.size(); ++i) {
        // for (int j = 0; j <= k; ++j) cout << dp[i][j] << " \n"[j == k];
    // }
}

int32_t main() {
    fastIO();
    init();
    
    int t = 1; // cin >> t;
    while (t--) solve();
    
    return 0;
}

Compilation message

anagramistica.cpp: In function 'void solve()':
anagramistica.cpp:59:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |     for (int i = 1; i <= nums.size(); ++i) {
      |                     ~~^~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 22988 KB Output is correct
2 Correct 18 ms 23076 KB Output is correct
3 Correct 14 ms 23060 KB Output is correct
4 Correct 16 ms 22988 KB Output is correct
5 Correct 19 ms 22972 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 22988 KB Output is correct
2 Correct 15 ms 23116 KB Output is correct
3 Correct 14 ms 23100 KB Output is correct
4 Correct 16 ms 23072 KB Output is correct

Subtask #3
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 22988 KB Output is correct
2 Correct 18 ms 23076 KB Output is correct
3 Correct 14 ms 23060 KB Output is correct
4 Correct 16 ms 22988 KB Output is correct
5 Correct 19 ms 22972 KB Output is correct
6 Correct 15 ms 22988 KB Output is correct
7 Correct 15 ms 23116 KB Output is correct
8 Correct 14 ms 23100 KB Output is correct
9 Correct 16 ms 23072 KB Output is correct
10 Correct 18 ms 23508 KB Output is correct
11 Correct 19 ms 22988 KB Output is correct
12 Correct 16 ms 22988 KB Output is correct
13 Correct 16 ms 23052 KB Output is correct
14 Correct 16 ms 23216 KB Output is correct
15 Correct 16 ms 23092 KB Output is correct
16 Correct 21 ms 24496 KB Output is correct
17 Correct 20 ms 23208 KB Output is correct
18 Correct 21 ms 22988 KB Output is correct