今日记录
188.买卖股票的最佳时机IV
class Solution {
public:
int maxProfit(int k, vector<int>& prices) {
vector<vector<int>> dp(prices.size(), vector<int>(2 * k + 1, 0));
for (int j = 1; j <= 2 * k - 1; j += 2) {
dp[0][j] = -prices[0];
}
for (int i = 1; i < prices.size(); i++) {
for (int j = 1; j <= 2 * k; j++) {
if (j % 2 == 0) {
dp[i][j] = max(dp[i - 1][j], dp[i - 1][j - 1] + prices[i]);
}
if (j % 2 == 1) {
dp[i][j] = max(dp[i - 1][j], dp[i - 1][j - 1] - prices[i]);
}
}
}
return dp[prices.size() - 1][2 * k];
}
};
309.最佳买卖股票时机含冷冻期
class Solution {
public:
int maxProfit(vector<int>& prices) {
int n = prices.size();
if (n == 0)
return 0;
vector<vector<int>> dp(n, vector<int>(4, 0));
dp[0][0] = -prices[0];
for (int i = 1; i < n; i++) {
dp[i][0] = max(dp[i - 1][0], max(dp[i - 1][3] - prices[i], dp[i - 1][1] - prices[i]));
dp[i][1] = max(dp[i - 1][1], dp[i - 1][3]);
dp[i][2] = dp[i - 1][0] + prices[i];
dp[i][3] = dp[i - 1][2];
}
return max(dp[n - 1][3], max(dp[n - 1][1], dp[n - 1][2]));
}
};
714.买卖股票的最佳时机含手续费
class Solution {
public:
int maxProfit(vector<int>& prices, int fee) {
vector<vector<int>> dp(prices.size(), vector<int>(2, 0));
dp[0][0] -= prices[0];
for (int i = 1; i < prices.size(); i++) {
dp[i][0] = max(dp[i - 1][0], dp[i - 1][1] - prices[i]);
dp[i][1] = max(dp[i - 1][1], dp[i - 1][0] + prices[i] - fee);
}
return max(dp[prices.size() - 1][0], dp[prices.size() - 1][1]);
}
};
总结
