CHFDORA : Jan 2020 long challenge video solution

editorial
,
1

Hey folks , here you can find the video editorial of
CHFDORA

Thank you guys for watching and keep coding.
CodeNCdode

4 Likes
2

thank man it helps a lot

3

You can refer to the detailed solution of DYNAMO here :smiley: Looking forward to your valuable feedback

1 Like
4

https://www.codechef.com/viewsolution/28944475

5

I have uploaded solution of that as well and for ENGLISH as well

1 Like
6

Clean easy to understand Chefdora solution
with comments and With Complete Analysis.
my submission

7

pick each element and find whether the left and right element (of current element ) is same and whether the upper and bottom element (of current element ) is same , if yes then increment count else return.

lli totalpali(vector<vector<int>> &a,lli n,lli m,lli i,lli j){ // i and j are current index
lli rowu = i-1; //rowup
lli rowd = i+1; //rowdown
lli coll = j-1; //col left
lli colr = j+1; // col right
lli cnt=0;
while((rowu>=0 && rowd<n && a[rowu][j]==a[rowd][j]) && (coll>=0 && colr<m && a[i][coll]==a[i][colr])){
    cnt++;
    rowu--;
    rowd++;
    coll--;
    colr++;
}
return cnt;
}
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You’re welcome brother.

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#include<bits/stdc++.h>
using namespace std;
int main()
{
int t,i,j,l,h,p,q;
cin>>t;
while(t–)
{
int n,m,res;
cin>>n>>m;
long long int a[n][m];
for(i=0;i<n;i++)
{
for(j=0;j<m;j++)
{
cin>>a[i][j];
}
}
res=n*m;
for(i=1;i<n-1;i++)
{
for(j=1;j<m-1;j++)
{
l=i-1;h=i+1;
p=j-1;q=j+1;
while(l>=0&&h<n&&a[i][p]==a[i][q]&&p>=0&&q<n&&a[l][j]==a[h][j])
{
res++;
l–;h++;
p–;q++;
}
}
}
cout<<res<<endl;
}
}
Is it wrong?

10

submit and check :slight_smile:

11

silly mistake:- written q<n instead of q<m :disappointed:

1 Like
12

i know these kinds of mistakes frustrate a lot , i can feel your pain

13

exactly what i needed

14

@waqar_ahmad224 Your efforts are enigmatic. :hearts:

1 Like
15

good initiative bro ,keep doing it .always supporting you @waqar_ahmad224

16

can we use manacher algorithm to solve this question . i used manacher algo and i got TLE.
My solution : CodeChef: Practical coding for everyone

17

thanks man for your appreciation

18

Good

19

Yes, Manacher’s algorithm can be used.
I have solved it with this algorithm myself and got AC.

My solution:

https://www.codechef.com/viewsolution/28924106

Just applied it on each row and saved the results for all elements.

After that applied it on each column and then added the minimum of the both traversal to the answer.

20

Thanks man , thanks for the support.