hdu 4162 Shape Number 最小表示法

题目链接

给一个字符串， 将它想象成一个环， 然后从环中任意一个位置断开， 求断开后字典序最小的那种情况。

直接上模板..

#include <iostream>
#include <vector>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <map>
#include <set>
#include <string>
#include <queue>
#include <stack>
#include <bitset>
using namespace std;
#define pb(x) push_back(x)
#define ll long long
#define mk(x, y) make_pair(x, y)
#define lson l, m, rt<<1
#define mem(a) memset(a, 0, sizeof(a))
#define rson m+1, r, rt<<1|1
#define mem1(a) memset(a, -1, sizeof(a))
#define mem2(a) memset(a, 0x3f, sizeof(a))
#define rep(i, n, a) for(int i = a; i<n; i++)
#define fi first
#define se second
typedef pair<int, int> pll;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int mod = 1e9+7;
const int inf = 1061109567;
const int dir[][2] = { {-1, 0}, {1, 0}, {0, -1}, {0, 1} };
int a[600005], n;
int getMin() {
    int i, j, k;
    for(i = 0, j = 1; i<n&&j<n; ) {
        for(k = 0; k<n&&a[i+k]==a[j+k]; k++)
            ;
        if(k>=n)
            break;
        if(a[i+k]<a[j+k])
            j += k+1;
        else
            i += k+1;
        if(i == j)
            j++;
    }
    return i;
}
int main()
{
    string s;
    while(cin>>s) {
        n = s.size();
        for(int i = 0; i<n; i++) {
            a[i] = s[i]-'0';
        }
        int tmp = a[0];
        for(int i = 0; i<n-1; i++) {
            a[i] = (a[i+1]-a[i]+8)%8;
        }
        a[n-1] = (tmp-a[n-1]+8)%8;
        for(int i = n; i<2*n; i++)
            a[i] = a[i-n];
        int pos = getMin();
        for(int i = pos; i<pos+n; i++)
            printf("%d", a[i]);
        cout<<endl;
    }
    return 0;
}