旋转一个数组以得到最大值。

陷阱就是：不能排序。须要模拟操作旋转，并设计公式计算旋转后的和。

要求是O(n)时间完毕。

原题：

https://www.hackerrank.com/challenges/game-of-rotation

#pragma once

#include <stdio.h>

class GameOfRotation

{

public:

	GameOfRotation()

	{

		int N = 0;

		scanf("%d", &N);

		int *A = new int[N];

		long long one = 0, sum = 0, ans = 0;

		for (int i = 0; i < N; i++)

		{

			scanf("%d", &A[i]);

			one += (long long)A[i];

			sum += (long long)(i+1) * (long long)A[i];

		}

		ans = sum;

		for (int i = 1; i < N; i++)

		{

			sum = sum - one + (long long)A[i-1] * (long long)N;

			ans = ans < sum ? sum : ans;

		}

		printf("%lld", ans);

		delete [] A;

	}

};

int gameOfRotation()

{

	GameOfRotation();

	return 0;

}