longest increasing subsequence DP solution

2023_11_16/longest-increasing-subsequence/src/main.rs

@@ -0,0 +1,31 @@
+impl Solution {
+    pub fn length_of_lis(nums: Vec<i32>) -> i32 {
+        let mut ans: Vec<i32> = Vec::new();
+        ans.push(nums[0]);
+
+        for &num in nums[1..].iter() {
+            if num > *ans.last().unwrap() {
+                ans.push(num);
+            } else {
+                let mut low = 0;
+                let mut high = ans.len() - 1;
+                while low < high {
+                    let mid = low + (high - low) / 2;
+                    if ans[mid] < num {
+                        low = mid + 1;
+                    } else {
+                        high = mid;
+                    }
+                }
+                ans[low] = num;
+            }
+        }
+        ans.len() as i32
+    }
+}
+
+struct Solution;
+
+fn main() {
+    assert_eq!(Solution::length_of_lis(vec![10, 9, 2, 5, 3, 7, 101, 18]), 4);
+}