Add TS for chapter of computational complexity

gogit2194 · Dec 15, 2022 · dbb6637 · dbb6637
1 parent b3d642f
commit dbb6637
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Showing 2 changed files with 60 additions and 2 deletions.
diff --git a/codes/typescript/chapter_computational_complexity/leetcode_two_sum.ts b/codes/typescript/chapter_computational_complexity/leetcode_two_sum.ts
@@ -0,0 +1,34 @@
+/*
+ * @Author: gyt95 ([email protected]) 
+ * @Date: 2022-12-15 11:26:38 
+ * @Last Modified by: gyt95 ([email protected])
+ * @Last Modified time: 2022-12-15 11:38:22
+ */
+
+function twoSumBruteForce(nums: number[], target: number): number[] {
+  let n = nums.length;
+  // 两层循环，时间复杂度 O(n^2)
+  for (let i = 0; i < n; i++) {
+    for (let j = i + 1; j < n; j++) {
+      if (nums[i] + nums[j] === target) {
+        return [i, j]
+      }
+    }
+  }
+  return [];
+};
+
+function twoSumHashTable(nums: number[], target: number): number[] {
+  // 辅助哈希表，空间复杂度 O(n)
+  let m: Map<number, number> = new Map()
+  // 单层循环，时间复杂度 O(n)
+  for (let i = 0; i < nums.length; i++) {
+    let index = m.get(nums[i])
+    if (index !== undefined) {
+      return [index, i]
+    } else {
+      m.set(target - nums[i], i)
+    }
+  }
+  return [];
+};
diff --git a/docs/chapter_computational_complexity/space_time_tradeoff.md b/docs/chapter_computational_complexity/space_time_tradeoff.md
@@ -96,7 +96,18 @@ comments: true
 === "TypeScript"
 
     ```typescript title="leetcode_two_sum.ts"
-
+    function twoSumBruteForce(nums: number[], target: number): number[] {
+      let n = nums.length;
+      // 两层循环，时间复杂度 O(n^2)
+      for (let i = 0; i < n; i++) {
+        for (let j = i + 1; j < n; j++) {
+          if (nums[i] + nums[j] === target) {
+            return [i, j]
+          }
+        }
+      }
+      return [];
+    };
     ```
 
 === "C"
@@ -199,7 +210,20 @@ comments: true
 === "TypeScript"
 
     ```typescript title="leetcode_two_sum.ts"
-
+    function twoSumHashTable(nums: number[], target: number): number[] {
+      // 辅助哈希表，空间复杂度 O(n)
+      let m: Map<number, number> = new Map()
+      // 单层循环，时间复杂度 O(n)
+      for (let i = 0; i < nums.length; i++) {
+        let index = m.get(nums[i])
+        if (index !== undefined) {
+          return [index, i]
+        } else {
+          m.set(target - nums[i], i)
+        }
+      }
+      return [];
+    };
     ```
 
 === "C"