CSES Minimal Rotation
// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
ifstream terminal("/dev/tty");
#define PP cerr<<"\033[1;30mpause...\e[0m",terminal.ignore();
#else
#define debug(x...)
#define Debug(x...)
#define PP
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define VI vector<int>
#define VII vector<vector<int>>
#define VIII vector<vector<vector<int>>>
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x), __VA_ARGS__})
#define cmax(x,...) x=max({(x), __VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define NaN (int)(0x8b88e1d0595d51d1)
#define double long double
#define int long long
#define uint unsigned long long
#define MAXN 200010
 
    vector<int> sa_is(const vector<int> &s, int upper) {
        int n = (int)(s.size());
        if (n == 0) return {};
        if (n == 1) return {0};
        if (n == 2) {
            if (s[0] < s[1]) return {0, 1};
            else return {1, 0};
        }
        vector<int> sa(n);
        vector<bool> ls(n);
        for (int i = n - 2; i >= 0; i--) {
            ls[i] = (s[i] == s[i + 1]) ? ls[i + 1] : (s[i] < s[i + 1]);
        }
        vector<int> sum_l(upper + 1), sum_s(upper + 1);
        for (int i = 0; i < n; i++) {
            if (!ls[i]) sum_s[s[i]]++;
            else sum_l[s[i] + 1]++;
        }
        for (int i = 0; i <= upper; i++) {
            sum_s[i] += sum_l[i];
            if (i < upper) sum_l[i + 1] += sum_s[i];
        }
        auto induce = [&](const vector<int>& lms) {
            fill(sa.begin(), sa.end(), -1);
            vector<int> buf(upper + 1);
            copy(sum_s.begin(), sum_s.end(), buf.begin());
            for (auto d : lms) {
                if (d == n) continue;
                sa[buf[s[d]]++] = d;
            }
            copy(sum_l.begin(), sum_l.end(), buf.begin());
            sa[buf[s[n - 1]]++] = n - 1;
            for (int i = 0; i < n; i++) {
                int v = sa[i];
                if (v >= 1 && !ls[v - 1]) {
                    sa[buf[s[v - 1]]++] = v - 1;
                }
            }
            copy(sum_l.begin(), sum_l.end(), buf.begin());
            for (int i = n - 1; i >= 0; i--) {
                int v = sa[i];
                if (v >= 1 && ls[v - 1]) {
                    sa[--buf[s[v - 1] + 1]] = v - 1;
                }
            }
        };
        vector<int> lms_map(n + 1, -1);
        int m = 0;
        for (int i = 1; i < n; i++) {
            if (!ls[i - 1] && ls[i]) {
                lms_map[i] = m++;
            }
        }
        vector<int> lms;
        lms.reserve(m);
        for (int i = 1; i < n; i++) {
            if (!ls[i - 1] && ls[i]) {
                lms.push_back(i);
            }
        }
        induce(lms);
        if (m) {
            vector<int> sorted_lms;
            sorted_lms.reserve(m);
            for (int v : sa) {
                if (lms_map[v] != -1) sorted_lms.push_back(v);
            }
            vector<int> rec_s(m);
            int rec_upper = 0;
            rec_s[lms_map[sorted_lms[0]]] = 0;
            for (int i = 1; i < m; i++) {
                int l = sorted_lms[i - 1], r = sorted_lms[i];
                int end_l = (lms_map[l] + 1 < m) ? lms[lms_map[l] + 1] : n;
                int end_r = (lms_map[r] + 1 < m) ? lms[lms_map[r] + 1] : n;
                bool same = true;
                if (end_l - l != end_r - r) {
                    same = false;
                } else {
                    while (l < end_l) {
                        if (s[l] != s[r]) break;
                        l++;
                        r++;
                    }
                    if (l == n || s[l] != s[r]) same = false;
                }
                if (!same) rec_upper++;
                rec_s[lms_map[sorted_lms[i]]] = rec_upper;
            }
    
            auto rec_sa = sa_is(rec_s, rec_upper);
            for (int i = 0; i < m; i++) sorted_lms[i] = lms[rec_sa[i]];
            induce(sorted_lms);
        }
        return sa;
    }
    
    pair<vector<int>, vector<int>> suffix_array(const string &s) {
        int n = (int)(s.size());
        vector<int> s2(n);
        for (int i = 0; i < n; i++) s2[i] = s[i];
        auto sa = sa_is(s2, 255);
        vector<int> rk(n); rep(i, 0, n) rk[sa[i]] = i;
        return {sa, rk};
    }

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    string s; cin >> s;
    int n = s.length();
    s = s + s;
    auto [sa, rk] = suffix_array(s);
    int minv = INF, minid = -1;
    rep(i, 0, n) {
        if (rk[i] < minv) minv = rk[i], minid = i;
    }
    cout << s.substr(minid, n) << endl;

    return 0;
}
No Comments

Send Comment Edit Comment


				
|´・ω・)ノ
ヾ(≧∇≦*)ゝ
(☆ω☆)
(╯‵□′)╯︵┴─┴
 ̄﹃ ̄
(/ω\)
∠( ᐛ 」∠)_
(๑•̀ㅁ•́ฅ)
→_→
୧(๑•̀⌄•́๑)૭
٩(ˊᗜˋ*)و
(ノ°ο°)ノ
(´இ皿இ`)
⌇●﹏●⌇
(ฅ´ω`ฅ)
(╯°A°)╯︵○○○
φ( ̄∇ ̄o)
ヾ(´・ ・`。)ノ"
( ง ᵒ̌皿ᵒ̌)ง⁼³₌₃
(ó﹏ò。)
Σ(っ °Д °;)っ
( ,,´・ω・)ノ"(´っω・`。)
╮(╯▽╰)╭
o(*////▽////*)q
>﹏<
( ๑´•ω•) "(ㆆᴗㆆ)
😂
😀
😅
😊
🙂
🙃
😌
😍
😘
😜
😝
😏
😒
🙄
😳
😡
😔
😫
😱
😭
💩
👻
🙌
🖕
👍
👫
👬
👭
🌚
🌝
🙈
💊
😶
🙏
🍦
🍉
😣
Source: github.com/k4yt3x/flowerhd
颜文字
Emoji
小恐龙
花!
Previous
Next