add: 更新下

Eric-art-coder · Eric-art-coder · commit b1396bf503a7 · 2023-10-28T14:38:30.000+08:00
diff --git a/labuladuo/14.最长公共前缀.js b/labuladuo/14.最长公共前缀.js
@@ -0,0 +1,26 @@
+/*
+ * @lc app=leetcode.cn id=14 lang=javascript
+ *
+ * [14] 最长公共前缀
+ */
+
+// @lc code=start
+/**
+ * @param {string[]} strs
+ * @return {string}
+ */
+var longestCommonPrefix = function(strs) {
+  if(strs.length === 0 ) return 0
+  let ans = strs[0]
+  for (let i = 1; i < strs.length; i++) {
+    let j = 0
+    for (; j < ans.length && j < strs[i].length; j++) {
+      if(ans[j] != strs[i][j]) break
+    }
+    ans = ans.substr(0, j)
+    if(ans === "") return ans
+  }
+  return ans
+};
+// @lc code=end
+
diff --git a/labuladuo/16.最接近的三数之和.js b/labuladuo/16.最接近的三数之和.js
@@ -0,0 +1,68 @@
+/*
+ * @lc app=leetcode.cn id=16 lang=javascript
+ *
+ * [16] 最接近的三数之和
+ */
+
+// @lc code=start
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+var threeSumClosest = function (nums, target) {
+  nums.sort((a, b) => a - b);
+  const n = nums.length;
+  let ans = 0;
+  let minDiff = Number.MAX_SAFE_INTEGER;
+  for (let i = 0; i < n - 2; i++) {
+      const x = nums[i];
+      if (i > 0 && x === nums[i - 1]) {
+          continue; // 优化三
+      }
+
+      // 优化一
+      let s = x + nums[i + 1] + nums[i + 2];
+      if (s > target) { // 后面无论怎么选，选出的三个数的和不会比 s 还小
+          if (s - target < minDiff) {
+              ans = s; // 由于下面直接 break，这里无需更新 minDiff
+          }
+          break;
+      }
+
+      // 优化二
+      s = x + nums[n - 2] + nums[n - 1];
+      if (s < target) { // x 加上后面任意两个数都不超过 s，所以下面的双指针就不需要跑了
+          if (target - s < minDiff) {
+              minDiff = target - s;
+              ans = s;
+          }
+          continue;
+      }
+
+      // 双指针
+      let j = i + 1, k = n - 1;
+      while (j < k) {
+          s = x + nums[j] + nums[k];
+          if (s === target) {
+              return target;
+          }
+          if (s > target) {
+              if (s - target < minDiff) { // s 与 target 更近
+                  minDiff = s - target;
+                  ans = s;
+              }
+              k--;
+          } else { // s < target
+              if (target - s < minDiff) { // s 与 target 更近
+                  minDiff = target - s;
+                  ans = s;
+              }
+              j++;
+          }
+      }
+  }
+  return ans;
+};
+// @lc code=end
+
