代码随想录——双指针/滑动窗口(二)

一.最长连续递增序列

go语言

func max(a,b int) int{
    if a>b{
        return a
    }
    return b
}

func findLengthOfLCIS(nums []int) int {
    n:=len(nums)
    maxlen:=0
    for l:=0;l<n;l++{
        r:=l+1
        for r<n&&nums[r]>nums[r-1]{
            r++
        }
        maxlen=max(r-l,maxlen)
    }
    return maxlen
}

int findLengthOfLCIS(vector<int>& nums) {
    int n = nums.size();
    int maxlen = 0;
    for (int l = 0; l < n; l++) {
        int r = l + 1;
        while (r < n && nums[r] > nums[r - 1]) {
            r++;
        }
        maxlen = max(r - l, maxlen);
    }
    return maxlen;
}

二.75. 颜色分类

func sortColors(nums []int)  {
    n:=len(nums)
    n0,n1:=0,0
    for i:=0;i<n;i++{
        num:=nums[i]
        nums[i]=2
        if num<2{
            nums[n1]=1
            n1++
        }
        if num<1{
            nums[n0]=0
            n0++
        }
    }
}

void sortColors(vector<int>& nums) {
    int n = nums.size();
    int n0 = 0, n1 = 0;
    for (int i = 0; i < n; i++) {
        int num = nums[i];
        nums[i] = 2;
        if (num < 2) {
            nums[n1++] = 1;
        }
        if (num < 1) {
            nums[n0++] = 0;
        }
    }
}

三. 904. 水果成篮

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}


func totalFruit(nums []int) int {
    cnt:=map[int]int{}
    maxlen:=0
    l:=0
    for r,x:=range(nums){
        cnt[x]++
        for len(cnt)>2{
            y:=nums[l]
            cnt[y]--
            if cnt[y]==0{
                delete(cnt,y)
            }
            l++
        }
        maxlen=max(maxlen,r-l+1)
    }
    return maxlen
}

class Solution {
public:
    int totalFruit(vector<int>& fruits) {
        unordered_map<int,int> map;
        int l=0;
        int maxlen=0;
        int n=fruits.size();
        for(int r=0;r<n;r++)
        {
            map[fruits[r]]++;
            while(map.size()>2)
            {
                auto y=map.find(fruits[l]);
                y->second--;
                if(y->second==0)
                {
                    map.erase(y);
                }
                l++;
            }
            maxlen=max(maxlen,r-l+1);
        }
        return maxlen;
    }
};