【HDOJ】4162 Shape Number

循环串的最小表示法。

/*  */
#include <iostream>
#include <string>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <vector>
#include <deque>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <climits>
#include <cctype>
#include <cassert>
#include <functional>
#include <iterator>
#include <iomanip>
using namespace std;
//#pragma comment(linker,"/STACK:102400000,1024000")

#define sti                set<int>
#define stpii            set<pair<int, int> >
#define mpii            map<int,int>
#define vi                vector<int>
#define pii                pair<int,int>
#define vpii            vector<pair<int,int> >
#define rep(i, a, n)     for (int i=a;i<n;++i)
#define per(i, a, n)     for (int i=n-1;i>=a;--i)
#define clr                clear
#define pb                 push_back
#define mp                 make_pair
#define fir                first
#define sec                second
#define all(x)             (x).begin(),(x).end()
#define SZ(x)             ((int)(x).size())
#define lson            l, mid, rt<<1
#define rson            mid+1, r, rt<<1|1

const int maxl = 3e5+5;
char M[8][8];
char s[maxl];
char d[maxl];
int len;

void init() {
    rep(i, 0, 8) {
        rep(j, 0, 8) {
            M[i][j] = (j-i+8)%8 + '0';
        }
    }
}

int minStr() {
    int i, j, k;
    int tmp;
    
    i = 0;
    j = 1;
    k = 0;
    while (i<len && j<len && k<len) {
        tmp = d[(i+k)%len] - d[(j+k)%len];
        if (tmp == 0) {
            ++k;
        } else {
            if (tmp < 0)
                j += k+1;
            else
                i += k+1;
            if (i == j)
                ++j;
            k = 0;
        }
    }

    return i<j ? i:j;
}

int main() {
    ios::sync_with_stdio(false);
    #ifndef ONLINE_JUDGE
        freopen("data.in", "r", stdin);
        freopen("data.out", "w", stdout);
    #endif
    
    int k;
    
    init();
    while (scanf("%s", s) != EOF) {
        len = strlen(s);
        s[len] = s[0];
        rep(i, 0, len) {
            d[i] = M[s[i]-'0'][s[i+1]-'0'];
        }
        #ifndef ONLINE_JUDGE
            d[len] = '';
            puts(d);
        #endif
        k = minStr();
        rep(i, 0, len) {
            putchar(d[(k+i)%len]);
        }
        putchar('
');
    }
    
    #ifndef ONLINE_JUDGE
        printf("time = %d.
", (int)clock());
    #endif
    
    return 0;
}