Cod sursa(job #2309599)

Utilizator AlexPop28Pop Alex-Nicolae AlexPop28 Data 29 decembrie 2018 13:59:03
Problema Prefix Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.17 kb
#include <bits/stdc++.h>
#define all(cont) cont.begin(), cont.end()
#define pb push_back
#define fi first
#define se second
#define DEBUG(x) cerr << (#x) << ": " << (x) << '\n'

using namespace std;

typedef pair <int, int> pii;
typedef vector <int> vi;
typedef long long ll;
typedef unsigned long long ull;

ifstream f ("prefix.in");
ofstream g ("prefix.out");

const int NMAX = 1e6 + 5;

int pi[NMAX];
char s[NMAX];

void computePi (int n) {
  pi[1] = 0;
  int cnd = 0;
  for (int i = 2; i <= n; ++i) {
    while (cnd && s[cnd + 1] != s[i]) {
      cnd = pi[cnd];
    }
    if (s[cnd + 1] == s[i]) {
      ++cnd;
    }
    pi[i] = cnd;
  }
}

void solveTest() {
  f.getline (s + 1, NMAX);
  int n = strlen (s + 1);
  computePi (n);

  for (int i = n; i >= 1; --i) {
    if (pi[i] == 0) continue;
    if ((i - (i - pi[i])) % (i - pi[i]) == 0) {
      g << i << '\n';
      return;
    }
  }
  g << "0\n";
}

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
#ifdef LOCAL_DEFINE
  freopen (".in", "r", stdin);
#endif

  int t;
  f >> t;
  f.get();
  while (t--) {
    solveTest();
  }

  f.close();
  g.close();
  return 0;
}