buy sell stocks 2

Author: jhideki

src/best_time_stock_cooldown.rs

@@ -0,0 +1,26 @@
+use std::collections::HashMap;
+pub struct Solution {}
+impl Solution {
+    pub fn max_profit(prices: Vec<i32>) -> i32 {
+        let mut map: HashMap<(i32, bool), i32> = HashMap::new();
+        Self::dfs(0, true, &prices, &mut map)
+    }
+
+    fn dfs(i: i32, buy: bool, prices: &Vec<i32>, map: &mut HashMap<(i32, bool), i32>) -> i32 {
+        if i > prices.len() as i32 {
+            return 0;
+        }
+        if map.contains_key(&(i, buy)) {
+            return *map.get(&(i, buy)).unwrap();
+        }
+        let cooldown = Self::dfs(i + 1, buy, prices, map);
+        if buy {
+            let val = Self::dfs(i + 1, !buy, prices, map) - prices[i as usize];
+            map.insert((i, buy), std::cmp::max(val, cooldown));
+        } else {
+            let sell = Self::dfs(i + 2, !buy, prices, map) + prices[i as usize];
+            map.insert((i, buy), std::cmp::max(sell, cooldown));
+        }
+        *map.get(&(i, buy)).unwrap()
+    }
+}

src/main.rs

@@ -1,2 +1,2 @@
-mod longest_common_subseq;
+mod best_time_stock_cooldown;
 fn main() {}