feat: non-overlapping-intervals

Author: gwbaik9717

non-overlapping-intervals/gwbaik9717.js

@@ -0,0 +1,47 @@
+// Time complexity: O(n^2)
+// Space complexity: O(n)
+
+/**
+ * @param {number[][]} intervals
+ * @return {number}
+ */
+var eraseOverlapIntervals = function (intervals) {
+  intervals.sort((a, b) => {
+    if (a[0] === b[0]) {
+      return a[1] - b[1];
+    }
+
+    return a[0] - b[0];
+  });
+
+  const dp = Array.from({ length: intervals.length }, () => 0);
+
+  dp[0] = 1;
+
+  for (let i = 1; i < intervals.length; i++) {
+    const [prevStart, prevEnd] = intervals[i - 1];
+    const [currentStart, currentEnd] = intervals[i];
+
+    // 구간이 겹칠 때
+    if (currentStart < prevEnd) {
+      // 현재를 포함할 때
+      let maxValue = 1;
+      for (let j = i - 1; j >= 0; j--) {
+        const [start, end] = intervals[j];
+
+        if (end <= currentStart) {
+          maxValue += dp[j];
+          break;
+        }
+      }
+
+      dp[i] = Math.max(dp[i - 1], maxValue);
+      continue;
+    }
+
+    // 구간이 겹치지 않을 때
+    dp[i] = dp[i - 1] + 1;
+  }
+
+  return intervals.length - dp.at(-1);
+};