oj.uz

Submission #584695

# Submission time Handle Problem Language Result Execution time Memory
584695 2022-06-27T20:31:22 Z tengiz05 Necklace (Subtask 1-3) (BOI19_necklace1) C++17
85 / 85
 282 ms 456 KB 
#include <bits/stdc++.h>

using i64 = long long;
using namespace std;

std::vector<int> z_function(std::string s) {
    int n = s.length();
    std::vector<int> z(n);
    for (int i = 1, l = 0, r = 0; i < n; i++) {
        if (i <= r)
            z[i] = std::min(r - i + 1, z[i - l]);
        while (i + z[i] < n && s[z[i]] == s[i + z[i]])
            ++z[i];
        if (i + z[i] - 1 > r)
            l = i, r = i + z[i] - 1;
    }
    return z;
}

std::vector<int> prefix_function(std::string s) {
    int n = s.size();
    std::vector<int> pi(n);
    for (int i = 1; i < n; i++) {
        int j = pi[i - 1];
        while (j > 0 && s[i] != s[j])
            j = pi[j - 1];
        if (s[i] == s[j])
            j++;
        pi[i] = j;
    }
    return pi;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    string a, b;
    cin >> a >> b;
    
    int n = a.size();
    int m = b.size();
    
    auto work = [&](string a, string b) -> array<int, 3> {
        array<int, 3> ans{-1, -1, -1};
        
        for (int i = 0; i < n; i++) {
            string S = a.substr(i, n - i) + "#" + b;
            string s1 = a.substr(0, i);
            string s2 = b;
            reverse(s1.begin(), s1.end());
            reverse(s2.begin(), s2.end());
            string T = s1 + "#" + s2;
            
            auto f = z_function(S);
            auto s = prefix_function(T);
            
            for (int j = 0; j < m; j++) {
                int k = f[n - i + 1 + j];
                if (j + k < m) {
                    int x = s[int(T.size()) - j - k - 1];
                    ans = max(ans, {k + x, i - x, j});
                } else {
                    ans = max(ans, {k, i, j});
                }
            }
        }
        
        return ans;
    };
    
    auto ans = work(a, b);
    reverse(b.begin(), b.end());
    auto res = work(a, b);
    res[2] = m - res[2] - res[0];
    
    ans = max(ans, res);
    
    cout << ans[0] << "\n";
    cout << ans[1] << " " << ans[2] << "\n";
    
    return 0;
}

Subtask #1
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 340 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 6 ms 316 KB Output is correct
7 Correct 6 ms 320 KB Output is correct
8 Correct 6 ms 340 KB Output is correct
9 Correct 6 ms 340 KB Output is correct
10 Correct 5 ms 372 KB Output is correct
11 Correct 5 ms 368 KB Output is correct
12 Correct 5 ms 340 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 316 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 6 ms 316 KB Output is correct
7 Correct 6 ms 320 KB Output is correct
8 Correct 6 ms 340 KB Output is correct
9 Correct 6 ms 340 KB Output is correct
10 Correct 5 ms 372 KB Output is correct
11 Correct 5 ms 368 KB Output is correct
12 Correct 5 ms 340 KB Output is correct
13 Correct 277 ms 340 KB Output is correct
14 Correct 247 ms 440 KB Output is correct
15 Correct 282 ms 448 KB Output is correct
16 Correct 266 ms 456 KB Output is correct
17 Correct 233 ms 340 KB Output is correct
18 Correct 245 ms 440 KB Output is correct
19 Correct 238 ms 440 KB Output is correct
20 Correct 251 ms 428 KB Output is correct
21 Correct 261 ms 448 KB Output is correct