제출 #500948

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
500948		dxz05	Palindromic Partitions (CEOI17_palindromic)	C++14	100 / 100	98 ms	19708 KiB

palindromic

#pragma GCC optimize("Ofast,O2,O3,unroll-loops")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

void debug_out() { cerr << endl; }

template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << "[" << H << "]";
    debug_out(T...);
}

#ifdef dddxxz
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define SZ(s) ((int)s.size())
#define all(x) (x).begin(), (x).end()
#define lla(x) (x).rbegin(), (x).rend()

clock_t startTime;

double getCurrentTime() {
    return (double) (clock() - startTime) / CLOCKS_PER_SEC;
}

#define MP make_pair

typedef long long ll;
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const double eps = 0.000001;
const int MOD = 998244353;
const int INF = 1000000101;
const long long LLINF = 1223372000000000555;
const int N = 1e6 + 3e2;
const int M = 222;

ll A = 998244353, B = 1e9 + 7;
ll pw[N];

void solve(int TC) {
    string s;
    cin >> s;

    int l = 0, r = s.size() - 1;
    int ans = 0, cnt = 0;
    ll lf = 0, rg = 0;
    while (l <= r){
        cnt++;
        lf = (lf * A + s[l]) % B;
        rg = (pw[cnt - 1] * s[r] + rg) % B;
        if (lf == rg){
            ans += 2 - (l == r);
//            cout << lf << ' ' << rg << endl;
            lf = rg = 0;
            cnt = 0;
        }
        l++;
        r--;
    }

    if (lf != 0) ans++;

    cout << ans << endl;

}

int main() {
    startTime = clock();
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

#ifdef dddxxz
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif

    pw[0] = 1;
    for (int i = 1; i < N; i++) pw[i] = pw[i - 1] * A % B;

    int TC = 1;
    cin >> TC;

    for (int test = 1; test <= TC; test++) {
        //debug(test);
        //cout << "Case #" << test << ": ";
        solve(test);
    }

    cerr << endl << "Time: " << int(getCurrentTime() * 1000) << " ms" << endl;

    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 20 / 20
• Subtask 3: 25 / 25
• Subtask 4: 40 / 40