LC 1438. Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit

class Solution {
public:
    int longestSubarray(vector<int>& nums, int limit) {
        int n=nums.size();
        deque<int> maxdq;
        deque<int> mindq;
        int right=0;
        int left=0;
        int res=1;
        while(right<n){
            while(!maxdq.empty() && nums[right]>nums[maxdq.back()]){
                maxdq.pop_back();
            }
            maxdq.push_back(right);
            while(!mindq.empty() && nums[right]<nums[mindq.back()]){
                mindq.pop_back();
            }
            mindq.push_back(right);
            while(nums[maxdq.front()]-nums[mindq.front()]>limit){
                if(maxdq.front()==left) maxdq.pop_front();
                if(mindq.front()==left) mindq.pop_front();
                ++left;
            }
            res=max(res,right-left+1);
            right++;
        }
        return res;
    }
};