Create 1776-car-fleet-ii.js

Author: everthis

1776-car-fleet-ii.js

@@ -0,0 +1,25 @@
+/**
+ * @param {number[][]} cars
+ * @return {number[]}
+ */
+var getCollisionTimes = function (cars) {
+  let n = cars.length,
+    t = 0,
+    i
+  const ans = Array(n)
+  for (let i = 0; i < n; i++) ans[i] = -1
+  const s = []
+  s[++t] = n - 1
+  for (let i = n - 2; ~i; i--) {
+    while (t && cars[s[t]][1] >= cars[i][1]) t--
+    while (
+      t > 1 &&
+      (cars[s[t]][0] - cars[i][0]) * (cars[i][1] - cars[s[t - 1]][1]) >
+        (cars[s[t - 1]][0] - cars[i][0]) * (cars[i][1] - cars[s[t]][1])
+    )
+      t--
+    if (t) ans[i] = (cars[s[t]][0] - cars[i][0]) / (cars[i][1] - cars[s[t]][1])
+    s[++t] = i
+  }
+  return ans
+}