add 128

Author: cch123

S0128-longest-consecutive-sequence/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "S0128-longest-consecutive-sequence"
+version = "0.1.0"
+authors = ["Xargin <cao1988228@163.com>"]
+edition = "2018"
+
+[dependencies]

S0128-longest-consecutive-sequence/src/main.rs

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+struct Solution;
+
+use std::collections::HashMap;
+use std::collections::HashSet;
+
+#[derive(Clone, Debug)]
+struct Bounds {
+    pub lower_bound: i32,
+    pub upper_bound: i32,
+}
+
+impl Solution {
+    pub fn longest_consecutive(nums: Vec<i32>) -> i32 {
+        // 记录每个元素对应的上界、下界
+        // 如果两个元素相连的话，那么这两个元素对应的上下界一定能连起来
+        let mut bounds_m: HashMap<i32, Bounds> = HashMap::new();
+
+        // 记录出现过的元素，如果元素之前出现过，没必要再处理了
+        let mut record_m: HashSet<i32> = HashSet::new();
+        let mut max_len = 0;
+        for num in nums {
+            if record_m.contains(&num) {
+                continue;
+            }
+
+            let left = num - 1;
+            let right = num + 1;
+            let mut new_bounds = Bounds {
+                upper_bound: num,
+                lower_bound: num,
+            };
+
+            if bounds_m.contains_key(&left) {
+                let left_bounds = bounds_m.get(&left).unwrap();
+                if left_bounds.upper_bound >= num {
+                    continue;
+                }
+
+                if left_bounds.upper_bound == left {
+                    // 可以合并
+                    new_bounds.lower_bound = left_bounds.lower_bound;
+                    bounds_m.remove(&left);
+                }
+            }
+
+            if bounds_m.contains_key(&right) {
+                let right_bounds = bounds_m.get(&right).unwrap();
+                if right_bounds.lower_bound <= num {
+                    continue;
+                }
+
+                if right_bounds.lower_bound == right {
+                    new_bounds.upper_bound = right_bounds.upper_bound;
+                    bounds_m.remove(&right);
+                }
+            }
+
+            bounds_m.insert(new_bounds.lower_bound, new_bounds.clone());
+            bounds_m.insert(new_bounds.upper_bound, new_bounds.clone());
+            max_len = max_len.max(new_bounds.upper_bound - new_bounds.lower_bound + 1);
+            record_m.insert(num);
+        }
+
+        max_len
+    }
+}
+
+fn main() {
+    dbg!(Solution::longest_consecutive(vec![100, 4, 200, 1, 3, 2]));
+}