两道类似题LeetCode152 和LeetCode714

152

int maxProduct(vector<int>& nums) {
    if(nums.size()==1)
        return nums[0];
    vector<vector<int>> dp(nums.size(),vector<int> (2));
    if(nums[0]<=0)
        dp[0][0]=nums[0];
    else
        dp[0][1]=nums[0];
    for(int i=1;i<nums.size();++i)
    {
            dp[i][1]=max(dp[i-1][1]*nums[i],dp[i-1][0]*nums[i])>nums[i]?max(dp[i-1][1]*nums[i],dp[i-1][0]*nums[i]):nums[i];
            dp[i][0]=min(dp[i-1][0]*nums[i],dp[i-1][1]*nums[i])<nums[i]?min(dp[i-1][0]*nums[i],dp[i-1][1]*nums[i]):nums[i];
    }
    int max=-100;
    for(int k=0;k<nums.size();++k)
    {
        if(dp[k][1]>max)
            max=dp[k][1];
    }
    return max;
}

714

int maxProfit(vector<int>& prices, int fee) {
    int cash=0;
    int buy=-prices[0];
    for(int i=1;i<prices.size();++i)
    {
        cash=cash>prices[i]+buy-fee?cash:prices[i]+buy-fee;

        buy=buy>cash-prices[i]?buy:cash-prices[i];
    }
    return cash;
}