Leetcode 3. Longest Substring Without Repeating Characters

這題用滑動視窗花了好久啊 , 可能晚上有點分心吧 , 差點就絕望了 , 主要是縮小視窗的時候沒有維護好 left 指標和 map , 寫虛擬碼的時候就寫錯了 ,
覆盤結果 : 下次寫完虛擬碼直接用虛擬碼走幾個能覆蓋大部分情況的測試用例

第一版將就下...至少比之前暴力破解快多了

func lengthOfLongestSubstring(s string) int {
    max:=0
    j:=0
    k:=-1
    curWmap:=make(map[uint8]int)
    curWsize:=0
    endIndex:=len(s)-1

    for ;k<endIndex; {
        k++
        if _,ok:=curWmap[s[k]];!ok{
            curWmap[s[k]]= k
            curWsize++
            max=maxC(curWsize,max)
        } else {
            curWsize++
            orij:=j
            j=curWmap[s[k]]+1
            curWsize=curWsize-(j-orij)
            for ;orij<j;orij++ {
                delete(curWmap,s[orij])
            }
            curWmap[s[k]]=k
            //sub:=curWmap[s[k]]
            //curWsize=curWsize - (sub-j)
            //orij:=j
            //curWmap[s[k]] = j
            //j=sub+1
            //
        }
    }
    return max

}

func maxC(l int,r int) int{
    if l>r {
        return l
    }
    return r
}

bobo sir的解 , 寫虛擬碼走一遍他的思路

虛擬碼嘗試走邏輯

if  window next not overflow  and window next is not in map
    r++
    put s[r] into map  

else
    window left step forward and remove from map (warn that r is not move ) , which is says that move left until no duplicate with s[r+1]

then calculate the window size by left , right pointer ,  find out the max size with currentMax

本作品採用《CC 協議》，轉載必須註明作者和本文連結