Create 2940-find-building-where-alice-and-bob-can-meet.js

Author: everthis

2940-find-building-where-alice-and-bob-can-meet.js

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+/**
+ * @param {number[]} heights
+ * @param {number[][]} queries
+ * @return {number[]}
+ */
+var leftmostBuildingQueries = function (heights, queries) {
+    const st = []
+    const [hs, qs] = [heights, queries]
+    let n = qs.length;
+    let ans = new Array(n).fill(-1);
+    let es = new Array(hs.length).fill().map(() => []);
+    for (let i = 0; i < n; i++) {
+        let x = qs[i][0];
+        let y = qs[i][1];
+        if (x > y) {
+            [x, y] = [y, x];
+        }
+        if (hs[y] > hs[x] || x === y) {
+            ans[i] = y;
+        } else {
+            es[y].push([hs[x], i]);
+        }
+    }
+
+    for (let i = hs.length - 1; i >= 0; i--) {
+        let n1 = st.length;
+        for (let [x, y] of es[i]) {
+            let p = search(x);
+            if (p < n1 && p >= 0) {
+                ans[y] = st[p][1];
+            }
+        }
+        while (st.length > 0 && st[st.length - 1][0] <= hs[i]) {
+            st.pop();
+        }
+        st.push([hs[i], i]);
+    }
+    return ans;
+
+  
+     function search(x) {
+        let l = 0;
+        let r = st.length - 1;
+        let ans = -1;
+        while (l <= r) {
+            let m = Math.floor((l + r) / 2);
+            if (st[m][0] > x) {
+                ans = Math.max(ans, m);
+                l = m + 1;
+            } else {
+                r = m - 1;
+            }
+        }
+        return ans;
+    }
+}