oj.uz

Submission #916044

# Submission time Handle Problem Language Result Execution time Memory
916044 2024-01-25T07:34:59 Z vjudge1 Palindromic Partitions (CEOI17_palindromic) C++17
100 / 100
 1860 ms 27352 KB 
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

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

#define db long double
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vi vector<int>
#define vl vector<ll>
#define vii vector<pii>
#define vll vector<pll>
#define endl '\n'
#define all(x) x.begin(), x.end()
#define fastio\
    ios_base::sync_with_stdio(0);\
    cin.tie(0);\
    cout.tie(0)\

#define int long long

const int sz = 1e6 + 5;
const int mod = 1e9 + 7;
string s;
int t, n, pre[sz], pw[sz], inv[sz];
map<pii, int> memo;

int sum(int a, int b){
    return (a + b) % mod;
}

int mult(int a, int b){
    return (a % mod) * (b % mod) % mod;
}

int sub(int a, int b){
    return (a - b + mod) % mod;
}

int binpow(int a, int b){
    if(b == 0)  return 1;
    if(b & 1)   return (a % mod * binpow(a, b - 1)) % mod;
    return binpow(a * a % mod, b / 2) % mod;
}

int get_hash(int l, int r){
    return mult(sub(pre[r], pre[l - 1]), inv[l - 1]);
}

signed main(){
    fastio;
    cin >> t;
    while(t--){
        cin >> s;
        n = s.size();
        s = ' ' + s;
        pw[0] = 1, inv[0] = 1;
        for(int i = 1; i <= n; i++){
            pw[i] = mult(pw[i - 1], 29);
            inv[i] = binpow(pw[i], mod - 2);
            pre[i] = sum(pre[i - 1], mult(s[i] - 'a' + 1, pw[i]));
        }
        int res = 0, p = 0;
        while(p < n / 2){
            int best = n - 2 * p;
            for(int i = 1; i <= n - 2 * p; i++){
                if(get_hash(p + 1, p + i) == get_hash(n - p - i + 1, n - p)){
                    best = i;
                    break;
                }
            }
            if(best == n - 2 * p)  res--;
            res += 2, p += best;
        }
        // cout << p << endl;
        if(n - 2 * p > 0) res++;
        cout << res << endl;
    }
}

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2392 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2392 KB Output is correct
6 Correct 1 ms 2392 KB Output is correct
7 Correct 1 ms 2392 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2392 KB Output is correct
6 Correct 1 ms 2392 KB Output is correct
7 Correct 1 ms 2392 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 19 ms 2648 KB Output is correct
11 Correct 11 ms 2648 KB Output is correct
12 Correct 18 ms 2716 KB Output is correct
13 Correct 16 ms 2652 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2392 KB Output is correct
6 Correct 1 ms 2392 KB Output is correct
7 Correct 1 ms 2392 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 19 ms 2648 KB Output is correct
11 Correct 11 ms 2648 KB Output is correct
12 Correct 18 ms 2716 KB Output is correct
13 Correct 16 ms 2652 KB Output is correct
14 Correct 1860 ms 26016 KB Output is correct
15 Correct 997 ms 25864 KB Output is correct
16 Correct 1755 ms 27352 KB Output is correct
17 Correct 983 ms 16972 KB Output is correct