leetcode 714. Best Time to Buy and Sell Stock with Transaction Fee

原题：

Your are given an array of integers prices, for which the i-th element is the price of a given stock on day i; and a non-negative integer fee representing a transaction fee.

You may complete as many transactions as you like, but you need to pay the transaction fee for each transaction. You may not buy more than 1 share of a stock at a time (ie. you must sell the stock share before you buy again.)

Return the maximum profit you can make.

代码如下：

int maxProfit(int* prices, int pricesSize, int fee) {
    int buyPrice=*prices;
    int sellPrice=0;
    int result=0;
    for(int n=1;n    {
        if(prices[n]-buyPrice>fee&&prices[n]>sellPrice)
        {
            sellPrice=prices[n];
        }
        if(sellPrice-prices[n]>=fee)
        {
            result+=sellPrice-buyPrice-fee;
            buyPrice=prices[n];
            sellPrice=0;
        }
        if(prices[n]            buyPrice=prices[n];
        //printf("A%d,%d,%d",buyPrice,sellPrice,result);
    }
    if(sellPrice>0)
        result+=sellPrice-buyPrice-fee;
    return result;

}

主要还是找到规律，动态规划的规律。

fee是个关键界限。