Create 403-frog-jump.js

Author: everthis

403-frog-jump.js

@@ -0,0 +1,32 @@
+/**
+ * @param {number[]} stones
+ * @return {boolean}
+ */
+const canCross = function(stones) {
+  for (let i = 3; i < stones.length; i++) {
+    if (stones[i] > stones[i - 1] * 2) {
+      return false
+    }
+  }
+  let count = new Set(stones)
+  let lastStone = stones[stones.length - 1]
+  let position = [0]
+  let jump = [0]
+  while (position.length > 0) {
+    let nextPosition = position.pop()
+    let nextDistance = jump.pop()
+    for (let i = nextDistance - 1; i <= nextDistance + 1; i++) {
+      if (i <= 0) {
+        continue
+      }
+      let nextStone = nextPosition + i
+      if (nextStone == lastStone) {
+        return true
+      } else if (count.has(nextStone)) {
+        position.push(nextStone)
+        jump.push(i)
+      }
+    }
+  }
+  return false
+}