for i in range(n - 1, -1, -1):

dp_buy = max(dp1_sell - prices[i], dp1_buy)

dp_sell = max(dp2_buy + prices[i], dp1_sell)

dp1_buy, dp1_sell = dp_buy, dp_sell

return dp1_buy

int dp_buy = Math.max(dp1_sell - prices[i], dp1_buy);

int dp_sell = Math.max(dp2_buy + prices[i], dp1_sell);

dp2_buy = dp1_buy;

dp1_buy = dp_buy;

dp1_sell = dp_sell;

}

int dp_buy = max(dp1_sell - prices[i], dp1_buy);

int dp_sell = max(dp2_buy + prices[i], dp1_sell);

dp2_buy = dp1_buy;

dp1_buy = dp_buy;

dp1_sell = dp_sell;

}

let dp_buy = Math.max(dp1_sell - prices[i], dp1_buy);

let dp_sell = Math.max(dp2_buy + prices[i], dp1_sell);

dp2_buy = dp1_buy;

dp1_buy = dp_buy;

dp1_sell = dp_sell;

}

int dp_buy = Math.Max(dp1_sell - prices[i], dp1_buy);

int dp_sell = Math.Max(dp2_buy + prices[i], dp1_sell);

dp2_buy = dp1_buy;

dp1_buy = dp_buy;

dp1_sell = dp_sell;

}