add: 增加一个算法题

Author: Eric-art-coder

src/string/readme.md

@@ -0,0 +1,2 @@
+总结：
+1、遇到那种重复的基本上都可以用Map

src/string/无重复字符的最长子串.ts

@@ -0,0 +1,56 @@
+function lengthOfLongsSubstring(s) {
+  let myMap = new Map()
+  let l = 0, r = 0, maxL = 0
+  while(r < s.length) {
+    if(myMap.has(s[r])) {
+      l = l > myMap.get(s[r]) + 1 ? l : myMap.get(s[r]) + 1
+    }
+    myMap.set(s[r], r)
+    maxL = Math.max(maxL, r - l + 1)
+    r++
+  }
+
+  return maxL
+}
+
+console.log(lengthOfLongsSubstring('abcabcbb')) // 'abc' 3
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+/**
+参考答案
+let map = new Map()
+let left = 0, right = 0, maxLen = 0
+while(right < s.length) {
+  let w = s[right]
+  if(map.has(w)) {
+    let i = map.get(w) + 1
+    left = left > i ? left : i
+  }
+  map.set(w, right)
+  maxLen = Math.max(maxLen, right-left+1)
+  right++
+}
+return maxLen
+
+ */