HDU - 6043 KazaQ's Socks（找规律）

题意：有n双袜子，编号1到n，放在衣柜里，每天早晨取衣柜中编号最小的袜子穿，晚上将这双袜子放在篮子里，当篮子里有n-1双袜子时，清洗袜子，直到第二天晚上才洗好，并将洗好的袜子重新放回衣柜。

分析：规律为

1、n=2时，1 2 1 2 1 2 1 2……

2、n=3时，1 2 3 1 2 1 3 1 2 1 3……

3、n=4时，1 2 3 4 1 2 3 1 2 4 1 2 3 1 2 4……

4、n=5时，1 2 3 4 5 1 2 3 4 1 2 3 5 1 2 3 4 1 2 3 5……

#include<cstdio>

#include<cstring>

#include<cstdlib>

#include<cctype>

#include<cmath>

#include<iostream>

#include<sstream>

#include<iterator>

#include<algorithm>

#include<string>

#include<vector>

#include<set>

#include<map>

#include<stack>

#include<deque>

#include<queue>

#include<list>

#define lowbit(x) (x & (-x))

const double eps = 1e-8;

inline int dcmp(double a, double b){

    if(fabs(a - b) < eps) return 0;

    return a > b ? 1 : -1;

}

typedef long long LL;

typedef unsigned long long ULL;

const int INT_INF = 0x3f3f3f3f;

const int INT_M_INF = 0x7f7f7f7f;

const LL LL_INF = 0x3f3f3f3f3f3f3f3f;

const LL LL_M_INF = 0x7f7f7f7f7f7f7f7f;

const int dr[] = {0, 0, -1, 1, -1, -1, 1, 1};

const int dc[] = {-1, 1, 0, 0, -1, 1, -1, 1};

const int MOD = 1e9 + 7;

const double pi = acos(-1.0);

const int MAXN = 10000 + 10;

const int MAXT = 10000 + 10;

using namespace std;

int main(){

    LL n, k;

    int kase = 0;

    while(scanf("%lld%lld", &n, &k) == 2){

        printf("Case #%d: ", ++kase);

        if(k <= n){

            printf("%lld\n", k);

            continue;

        }

        LL a = (k - n) / (n - 1);

        LL b = (k - n) % (n - 1);

        if(b != 0){

            printf("%lld\n", b);

        }

        else{

            if(a & 1){

                printf("%lld\n", n - 1);

            }

            else{

                printf("%lld\n", n);

            }

        }

    }

    return 0;

}