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/**
 * 
 * <p>
 * ClassName SolutionBestTimeToBuyAndSellStock
 * </p>
 * <p>
 * Description Say you have an array for which the ith element is the price of a given stock on day i.
 * 
 * If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm to find the maximum profit.
 * </p>
 * 
 * @author wangxu wangx89@126.com
 *         <p>
 *         Date 2014-9-11 下午09:06:21
 *         </p>
 * @version V1.0
 * 
 */
public class SolutionBestTimeToBuyAndSellStock {
	public int maxProfit(int[] prices) {
		if (prices.length == 0) {
			return 0;
		}
		int min = prices[0];// 将第一个值看作是最低值
		int profit = 0;// 目前的利润为0
		for (int i = 1; i < prices.length; i++) {
			if (prices[i] - min > profit) {
				profit = prices[i] - min;
			} else {
				if (prices[i] < min) {
					min = prices[i];
				}

			}
		}
		return profit;
	}
}

Best Time To Buy And Sell Stock