Best Time to Buy and Sell Stock @LeetCode

package Level2;

/**
 * Best Time to Buy and Sell Stock 
 * 
 * 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.
 */
public class S121 {

	public static void main(String[] args) {

	}
	
	public int maxProfit(int[] prices) {
		// 当没有任何prices信息的情况
		if(prices.length == 0){
			return 0;
		}
        int min = prices[0];		// 记录最小买入价的index
        int maxProfit = 0;			// 记录最大profit
        
        for(int i=1; i<prices.length; i++){
        	// 更新最小买入价
        	if(prices[i] < min){
        		min = prices[i];
        	}
        	
        	// 计算当前利润
        	int currentProfit = prices[i] - min;
        	// 如果当前利润超过最大利润，更新最大利润
        	if(currentProfit > maxProfit){
        		maxProfit = currentProfit;
        	}
        }
        
        return maxProfit;
    }

}