class Solution {
public:
    bool isIdealPermutation(vector<int>& nums) {
        int n = nums.size();
        int minx = nums[n-1];
        for(int i=n-3;i>=0;i--)
        {
            if(nums[i]>minx)
            return false;

            minx = min(minx,nums[i+1]);
        }

        return true;
    }
};