結果
問題 | No.2858 Make a Palindrome |
ユーザー |
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提出日時 | 2024-08-25 14:28:16 |
言語 | C++23 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 83 ms / 3,000 ms |
コード長 | 2,729 bytes |
コンパイル時間 | 3,058 ms |
コンパイル使用メモリ | 276,024 KB |
実行使用メモリ | 6,944 KB |
最終ジャッジ日時 | 2024-08-25 14:28:22 |
合計ジャッジ時間 | 5,221 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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ファイルパターン | 結果 |
---|---|
other | AC * 40 |
ソースコード
#include<bits/stdc++.h>namespace {#pragma GCC diagnostic ignored "-Wunused-function"#include<atcoder/all>#pragma GCC diagnostic warning "-Wunused-function"using namespace std;using namespace atcoder;#define rep(i,n) for(int i = 0; i < (int)(n); i++)#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)#define all(x) begin(x), end(x)#define rall(x) rbegin(x), rend(x)template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }using ll = long long;using P = pair<int,int>;using VI = vector<int>;using VVI = vector<VI>;using VL = vector<ll>;using VVL = vector<VL>;template <class T>vector<int> Manacher(const T& s) {const int n = s.size();vector<int> res(n);for (int i = 0, r = 1; i < n;) {int l = 2 * i - r;while (0 <= l && r < n && s[l] == s[r]) l--, r++;res[i] = r - i;if (++i != r) {int j = i - 2;while (i + res[j] < r) res[i++] = res[j--];}}return res;}template <class T>vector<int> Manacher_cursor(const T& s) {const int n = s.size();vector<int> res(n + 1);for (int i = 1, r = 1; i < n;) {int l = 2 * i - r;while (l && r < n && s[l - 1] == s[r]) l--, r++;res[i] = r - i;if (i++ != r) {int j = i - 2;while (i + res[j] < r) res[i++] = res[j--];} else {r = i;}}return res;}auto floor_div(signed_integral auto x, signed_integral auto y) {return x / y - ((x ^ y) < 0 && x % y != 0);}template <integral T>T floor_div(T x, unsigned_integral auto y) {return x >= 0 ? T(x / y) : -T(-x / y + (-x % y != 0));}auto ceil_div(signed_integral auto x, signed_integral auto y) {return x / y + ((x ^ y) >= 0 && x % y != 0);}template <integral T>T ceil_div(T x, unsigned_integral auto y) {return x >= 0 ? T(x / y + (x % y != 0)) : -T(-x / y);}} int main() {ios::sync_with_stdio(false);cin.tie(0);int tt;cin >> tt;while (tt--) {int n, m;string s;cin >> n >> m >> s;s = s + s + s;constexpr int INF = 1001001001;int ans = INF;{auto mc = Manacher_cursor(s);rep(c, 3 * n + 1) {if (mc[c] >= n || 2 * mc[c] >= m) {int l = c - (m + 1) / 2, r = c + (m + 1) / 2;chmin(ans, floor_div(r - 1, n) - floor_div(l, n) + 1);}}}{auto me = Manacher(s);rep(c, 3 * n) {if (me[c] >= n || 2 * me[c] - 1 >= m) {int l = c - m / 2, r = c + m / 2;chmin(ans, floor_div(r, n) - floor_div(l, n) + 1);}}}if (ans == INF) ans = -1;cout << ans << '\n';}}