Runtime 290 ms (Top 80.0%) | Memory 87.0 MB (Top 20.0%)

Author: AnasImloul

scripts/algorithms/M/Minimum Operations to Make a Subsequence/Minimum Operations to Make a Subsequence.js

@@ -0,0 +1,41 @@
+const minOperations = function (targets, arr) {
+  const map = {};
+  const n = targets.length;
+  const m = arr.length;
+  targets.forEach((target, i) => (map[target] = i));
+
+//map elements in arr to index found in targets array
+  const arrIs = arr.map(el => {
+    if (el in map) {
+      return map[el];
+    } else {
+      return -1;
+    }
+  });
+
+//create a LIS table dp whose length is the longest increasing subsequence
+  const dp = [];
+
+  for (let i = 0; i < m; i++) {
+    const curr = arrIs[i];
+    if (curr === -1) continue;
+    if (!dp.length || curr > dp[dp.length - 1]) {
+      dp.push(curr);
+    } else if (curr < dp[0]) {
+      dp[0] = curr;
+    } else {
+      let l = 0;
+      let r = dp.length;
+      while (l < r) {
+        const mid = Math.floor((l + r) / 2);
+        if (arrIs[i] <= dp[mid]) {
+          r = mid;
+        } else {
+          l = mid + 1;
+        }
+      }
+      dp[r] = curr;
+    }
+  }
+  return n-dp.length;
+};