Create 691-stickers-to-spell-word.js

Author: everthis

691-stickers-to-spell-word.js

@@ -0,0 +1,60 @@
+/**
+ * @param {string[]} stickers
+ * @param {string} target
+ * @return {number}
+ */
+const minStickers = function(stickers, target) {
+  const isEqual = (arr1, arr2) => {
+    for (let i = 0; i < arr1.length; ++i) if (arr1[i] !== arr2[i]) return false
+    return true
+  }
+
+  const minus = (arr1, arr2) => {
+    let res = []
+    for (let i = 0; i < arr1.length; ++i)
+      res[i] = arr1[i] <= 0 ? arr1[i] : arr1[i] - arr2[i]
+    return res
+  }
+
+  const isAllNonpositive = arr => {
+    return arr.every(item => item <= 0)
+  }
+
+  const getString = arr => {
+    return arr.reduce((acc, cur, idx) => {
+      if (cur > 0) return acc + String.fromCharCode(idx + 97).repeat(cur)
+      else return acc
+    }, '')
+  }
+
+  let ss = stickers.map(word => {
+    let tmp = new Array(26).fill(0)
+    for (let i = 0; i < word.length; ++i) tmp[word.charCodeAt(i) - 97]++
+    return tmp
+  })
+  let root = new Array(26).fill(0)
+  for (let i = 0; i < target.length; ++i) root[target.charCodeAt(i) - 97]++
+  let cache = new Set()
+  let queue = [root]
+  let size = 0,
+    level = 0,
+    front = null
+  while (queue.length !== 0) {
+    size = queue.length
+    while (size--) {
+      front = queue.shift()
+      for (let w of ss) {
+        let t = minus(front, w)
+        let str = getString(t)
+        if (isEqual(t, front) || cache.has(str)) continue
+        if (isAllNonpositive(t)) return level + 1
+        else {
+          queue.push(t)
+          cache.add(str)
+        }
+      }
+    }
+    level++
+  }
+  return -1
+}