increase three solution

Author: EternalChildren

maxProfit/rust/Cargo.lock

@@ -0,0 +1,7 @@
+[package]
+name = "rust"
+version = "0.1.0"
+authors = ["EternalChildren <colin.zcn@outlook.com>"]
+edition = "2018"
+
+[dependencies]

maxProfit/rust/Cargo.toml

@@ -0,0 +1,56 @@
+// 0ms 2.2MB
+pub fn max_profit_fastly(prices: Vec<i32>) -> i32 {
+    if prices.len() < 2 {
+        return 0;
+    }
+    let mut ans = 0;
+    let mut min = std::i32::MAX;
+
+    for p in prices {
+        let profit = std::cmp::max(p - min, 0);
+        if profit > ans {
+            ans = profit;
+        }
+        min = std::cmp::min(min, p);
+    }
+    ans
+}
+
+// 72ms 2.3MB
+pub fn max_profit(prices: Vec<i32>) -> i32 {
+    if prices.len() < 2 {
+        return 0;
+    }
+    let mut ans = 0;
+
+    for i in 0..prices.len() {
+        for j in i + 1..prices.len() {
+            let dif = prices[j] - prices[i];
+            if dif > ans {
+                ans = dif;
+            }
+        }
+    }
+    println!("res is {}", ans);
+    ans
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let vec = vec![7, 1, 5, 3, 6, 4];
+        assert_eq!(max_profit(vec), 5);
+        let vec1 = vec![7, 6, 4, 3, 1];
+        assert_eq!(max_profit(vec1), 0);
+    }
+
+    #[test]
+    fn quickly() {
+        let vec = vec![7, 1, 5, 3, 6, 4];
+        assert_eq!(max_profit_fastly(vec), 5);
+        let vec1 = vec![7, 6, 4, 3, 1];
+        assert_eq!(max_profit_fastly(vec1), 0);
+    }
+}

maxProfit/rust/src/lib.rs

@@ -0,0 +1,7 @@
+[package]
+name = "rust"
+version = "0.1.0"
+authors = ["EternalChildren <colin.zcn@outlook.com>"]
+edition = "2018"
+
+[dependencies]

maxProfitII/rust/Cargo.lock

@@ -0,0 +1,29 @@
+// 0ms 2.2MB
+pub fn max_profit(prices: Vec<i32>) -> i32 {
+    if prices.len() < 2 {
+        return 0;
+    }
+    let mut ans = 0;
+    for i in 0..prices.len() - 1 {
+        if prices[i] < prices[i + 1] {
+            ans += prices[i + 1] - prices[i];
+        }
+    }
+    println!("ans is {}", ans);
+    ans
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let vec = vec![7, 1, 5, 3, 6, 4];
+        assert_eq!(max_profit(vec), 7);
+        let vec1 = vec![1, 2, 3, 4, 5];
+        assert_eq!(max_profit(vec1), 4);
+        let vec2 = vec![7, 6, 4, 3, 1];
+        assert_eq!(max_profit(vec2), 0);
+    }
+}

maxProfitII/rust/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "rust"
+version = "0.1.0"
+authors = ["EternalChildren <colin.zcn@outlook.com>"]
+edition = "2018"
+
+[dependencies]

maxProfitII/rust/src/lib.rs

@@ -0,0 +1,37 @@
+// 0ms 2.2MB 大佬代码 暂时还不太明白
+pub fn max_profit(prices: Vec<i32>) -> i32 {
+    let mut max_profit_1 = 0;
+    let mut max_profit_2 = 0;
+    let mut lowest_buy_price_1 = std::i32::MIN;
+    let mut lowest_buy_price_2 = std::i32::MIN;
+
+    for p in prices {
+        lowest_buy_price_1 = std::cmp::max(lowest_buy_price_1, -p);
+        max_profit_1 = std::cmp::max(max_profit_1, lowest_buy_price_1 + p);
+        lowest_buy_price_2 = std::cmp::max(lowest_buy_price_2, max_profit_1 - p);
+        max_profit_2 = std::cmp::max(max_profit_2, p + lowest_buy_price_2);
+    }
+
+    max_profit_2
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let vec = vec![3, 3, 5, 0, 0, 3, 1, 4];
+        assert_eq!(max_profit(vec), 6);
+        let vec1 = vec![1, 2, 3, 4, 5];
+        assert_eq!(max_profit(vec1), 4);
+        let vec2 = vec![7, 6, 4, 3, 1];
+        assert_eq!(max_profit(vec2), 0);
+    }
+
+    #[test]
+    fn last() {
+        let vec = vec![1, 2, 4, 2, 5, 7, 2, 4, 9, 0];
+        assert_eq!(max_profit(vec), 13);
+    }
+}