diff options
Diffstat (limited to 'best_time_buy_sell_stock3.c')
-rw-r--r-- | best_time_buy_sell_stock3.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/best_time_buy_sell_stock3.c b/best_time_buy_sell_stock3.c new file mode 100644 index 0000000..8867f7b --- /dev/null +++ b/best_time_buy_sell_stock3.c @@ -0,0 +1,44 @@ +// 123. Best Time to Buy and Sell Stock III +#include "leetcode.h" + +/* + * you are given an array 'prices' where 'prices[i]' is the price of a given + * stock on the i'th day. find the maximum profit you can achieve. you may + * complete at most two transactions. note, you may not engage in multiple + * transactions simultaneously. + */ + +int maxProfit(int *prices, int pricesSize) { + int *s1 = (int *)calloc(pricesSize, sizeof(int)); + int *s2 = (int *)calloc(pricesSize, sizeof(int)); + int max = INT_MIN, min = prices[0]; + for (int i = 1; i < pricesSize - 1; i++) { + if (min > prices[i]) + min = prices[i]; + if (max < prices[i] - min) + max = prices[i] - min; + s1[i] = max; + } + min = INT_MIN, max = prices[pricesSize - 1]; + s2[pricesSize - 1] = 0; + for (int i = pricesSize - 2; i >= 0; i--) { + if (prices[i] > max) + max = prices[i]; + if (min < max - prices[i]) + min = max - prices[i]; + s2[i] = min; + } + max = INT_MIN; + for (int i = 0; i < pricesSize; i++) + max = max < s1[i] + s2[i] ? s1[i] + s2[i] : max; + free(s1), free(s2); + return max; +} + +int main() { + int p1[] = {3, 3, 5, 0, 0, 3, 1, 4}, p2[] = {1, 2, 3, 4, 5}, + p3[] = {7, 6, 4, 3, 1}; + printf("%d\n", maxProfit(p1, ARRAY_SIZE(p1))); // expect: 6 + printf("%d\n", maxProfit(p2, ARRAY_SIZE(p2))); // expect: 4 + printf("%d\n", maxProfit(p3, ARRAY_SIZE(p3))); // expect: 0 +} |