Submission #250638

# Submission time Handle Problem Language Result Execution time Memory
250638 2020-07-18T14:50:51 Z Sorting Palindromic Partitions (CEOI17_palindromic) C++14
60 / 100
10000 ms 21644 KB
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int k_N = 1e6 + 3;
const int cnt_Mod = 1;
const array<ll, cnt_Mod> k_Mod{(int)1e9 + 7}, k_Base{293};

int dp[k_N];
string s;
int n;

array<ll, cnt_Mod> h[k_N], b_pow[k_N];
vector<int> pos[256];
int idx[256];

ll get_hash(int l, int r, int idx){
    if(l == 0) return h[r][idx];
    ll ans = (h[r][idx] - h[l - 1][idx] * b_pow[r - l + 1][idx]) % k_Mod[idx];
    return (ans < 0) ? (ans + k_Mod[idx]) : ans;
}

bool equal(int l1, int r1, int l2, int r2){
    for(int i = 0; i < cnt_Mod; ++i)
        if(get_hash(l1, r1, i) != get_hash(l2, r2, i))
            return false;
    return true;
}

void init_hashing(){
    for(int i = 0; i < n; ++i){
        for(int j = 0; j < cnt_Mod; ++j){
            if(i == 0)
                h[i][j] = s[i];
            else
                h[i][j] = (h[i - 1][j] * k_Base[j] + s[i]) % k_Mod[j];
        }
    }

    for(int i = 0; i < n; ++i){
        for(int j = 0; j < cnt_Mod; ++j){
            if(i == 0)
                b_pow[i][j] = 1;
            else
                b_pow[i][j] = b_pow[i - 1][j] * k_Base[j] % k_Mod[j];
        }
    }
}

void solve(){
    cin >> s;
    n = (int)s.size();

    if(n == 1){
        cout << "1\n";
        return;
    }


    init_hashing();
    for(int i = 0; i < n; ++i)
        pos[s[i]].push_back(i);

    int mid = (n - 1) / 2, mid2 = (n - 2) / 2;
    dp[mid + 1] = 0;
    for(int i = mid; i >= 0; --i){
        dp[i] = 1;
        for(int k = (int)pos[s[i]].size() - 1; k >= 0; --k){
            int j = pos[s[i]][k];
            if(j > n - i - 1) continue;
            if(n - j - 1 >= j) break;
            
            if(dp[n - j] + 2 <= dp[i]) break;

            if(equal(i, n - j - 1, j, n - i - 1))
                dp[i] = max(dp[n - j] + 2, dp[i]);
        }
    }

    cout << dp[0] << "\n";
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int t;
    cin >> t;

    while(t--)
        solve();
}

Compilation message

palindromic.cpp: In function 'void solve()':
palindromic.cpp:64:17: warning: array subscript has type 'char' [-Wchar-subscripts]
         pos[s[i]].push_back(i);
                 ^
palindromic.cpp:70:34: warning: array subscript has type 'char' [-Wchar-subscripts]
         for(int k = (int)pos[s[i]].size() - 1; k >= 0; --k){
                                  ^
palindromic.cpp:71:29: warning: array subscript has type 'char' [-Wchar-subscripts]
             int j = pos[s[i]][k];
                             ^
palindromic.cpp:66:28: warning: unused variable 'mid2' [-Wunused-variable]
     int mid = (n - 1) / 2, mid2 = (n - 2) / 2;
                            ^~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
10 Correct 107 ms 1164 KB Output is correct
11 Correct 156 ms 888 KB Output is correct
12 Correct 90 ms 1140 KB Output is correct
13 Correct 56 ms 1016 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
10 Correct 107 ms 1164 KB Output is correct
11 Correct 156 ms 888 KB Output is correct
12 Correct 90 ms 1140 KB Output is correct
13 Correct 56 ms 1016 KB Output is correct
14 Execution timed out 10094 ms 21644 KB Time limit exceeded
15 Halted 0 ms 0 KB -