3sum

Author: jun0811

3sum/jun0811.js

@@ -0,0 +1,38 @@
+/**
+ * @param {number[]} nums
+ * @return {number[][]}
+ */
+
+// 중복 제거 중점..
+var threeSum = function (nums) {
+  nums.sort((a, b) => a - b);
+  const result = [];
+
+  for (let i = 0; i < nums.length - 2; i++) {
+    if (i > 0 && nums[i] === nums[i - 1]) continue;
+
+    let left = i + 1;
+    let right = nums.length - 1;
+
+    while (left < right) {
+      const sum = nums[i] + nums[left] + nums[right];
+
+      if (sum === 0) {
+        result.push([nums[i], nums[left], nums[right]]);
+
+        // 중복 미리 제거
+        while (left < right && nums[left] === nums[left + 1]) left++;
+        while (left < right && nums[right] === nums[right - 1]) right--;
+
+        left++;
+        right--;
+      } else if (sum < 0) {
+        left++;
+      } else {
+        right--;
+      }
+    }
+  }
+
+  return result;
+};