Can You Please tell me the hint how to solve this problem

#1


Can You Please tell me the hint how to solve this problem
WITHOUT THE SOLUTION
Or How you think about this solution
From Basic approach to the most optimized approach.

#2

hello @cbcao263

in this problem we are allowed to modify atmost 1 element to make array non decreasing /sorted.

so we can split this problem in three cases.

a) no modification needed
if given array is already non decreasing then return true otherwise look for case b
b) one modification needed
here we will go to each element of array (say index is i)
and will check whether array from index [0,i-1] and [i+1,…n-1] is sorted and a[i-1] <=a[i+1] if this hold then we return true

if even after complete iteration we dont find any such index i ,then simply we return false.

c) not possible (if above two fails)

#3

Okayy Sir.

Sir is it like pehle waala part sorted hai
fir ek element jisne kaam khrab kiya
nd Then After all array sorted.

And What I did is: -
I took 2 variables inc=0,dec=0
And If I found a[i+1]>a[i] inc++
else ifa[i+1]<a[i] dec++.
Like that.
I think that too will be correct.

#4

Bro One More doubt, What If I Pause the course.
And What If I directly post the doubt here.
Will it get solved or not?

#5

i m not sure , u can ask it from support team
email->[email protected]

#6

yeah this should work

#7 
public:
    bool checkPossibility(vector<int>& nums) {
        int n=nums.size();
        int inc=0,dec=0;
        for(int i=0;i<n-1;i++)
        {
            int d=nums[i+1]-nums[i];
            if(d<0)
                dec++;
            else
                inc++;
        }
        if(dec==1)
            return true;
        else
            return false;
    }
};

This is what I used, But it’s giving error on this one.
[3,4,2,3]

#8

it needs two modifications

if i is the false element of the array then comparee a[i-1] with a[i+1] if a[i-1]<=a[i+1] then increment ur dec otherwise return false

#9

Smjha nhi Sir

Aur yeh kisliye

#10

element jiske wajah se gadbad ho rahi hai.

to ensure ki baaki element sorted hai ya nahi.

1 3 1 4 6 ( 1 is the false element , to usko hata ke baaki a[i-1] <=a[i+1] condition follow karna chaiye otherwise single modification mein possible nahi hain)
example->
1 3 1 2 6 (yaha pe 1 false element hai right? but a[i-1]<=a[i+1] nahi hai ( 3 < = 2 nahi hai ) isiliye ye possible nahi hai)

#11

ton mtlb jo loop hain usme ek if else condition lgaadu
if a[i-1]<=a[i+1]
return false;
bas shi hain?

#12

ha agar ye condition satisfy nahi ho rahi to returrn false
kam kar jayega

#13

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