A-D | Educational Codeforces Round 163 Solutions | Tandem Repeats? | Arrow Path Array Fix | Abhinav

[@JamilAhmad-ld3br]

extra ordinary explanation

[@AbhinavAwasthi]

Thanks a lot

[@nandanbhowmick1825]

Problem C explanation was really good. Thanks a lot.

[@AbhinavAwasthi]

Thanks a lot

[@GauravDuseja-t6q]

Very Good explanation bhaiya

[@Voldemort-m8x]

For problem C we can simply check one condition that if if we have '

[@aankie]

if i reach specialist...i will only come to salute you man..! glad i found you...regular viewer ...let see

[@AbhinavAwasthi]

Sure bro, you will one day Keep trying 🙌🏻

[@sainath5131]

Helpfull

[@AbhinavAwasthi]

Thanks

[@shubhamdugar8249]

great editorials. Solved C using DP

[@AbhinavAwasthi]

Great thanks

[@AbjSir]

send code or tell your username on codeforces i'm curious

[@mmbmmbmmb]

send

[@imteajsaimun4134]

how pls explain

[@saumyaranjan9256]

@@imteajsaimun4134 void solve(){ ll t; cin>>t; while(t--){ ll n; cin>>n; bool dp[2][n]; memset(dp, false, sizeof(dp)); // tldr : 0123 dp[1][n-1] = true; vector a(2, vector(n)); for(ll i = 0; ix; if(x == '>'){ a[i][j] = 1; } else a[i][j] = -1; } } dp[0][n-1] = true; dp[1][n-2] = true; dp[0][n-2] = (a[1][n-2] == 1 ? true : false); vector dr = {-1, 0, 1}; vector dc = {0, 1, 0}; for(ll col = n-3; col>=0; col--){ for(ll row = 0; row

[@itsmepratham2712]

ha ha at 27:31 i realized how easy the problem is and tricky

[@AbhinavAwasthi]

🙆🏻‍♂️😂

[@codecreateriitp4751]

Thanks bhaiya i like your 3rd question concept most of the people use dfs of this question

[@AbhinavAwasthi]

Thanks 🙌🏻

[@prime_great]

Sir in problem C If test case is like this >>< >

[@ChiragWadwa]

n is always even

[@AbhinavAwasthi]

Can you send the code

[@prime_great]

@@AbhinavAwasthi sure.... #include using namespace std ; #define MOD 1000000007 ; typedef long long ll ; #define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0) ; void solve(){ ll n ; cin>>n ; string str ; vector main ; cin>>str ; main.push_back(str) ; cin>>str ; main.push_back(str) ; vector dp(2 , vector (n , -1)) ; dp[0][n - 1] = 1 ; dp[1][n - 2] = 1 ; dp[1][n - 1] = 1 ; if(main[1][n - 2] == '>') dp[0][n - 2] = 1 ; for(int i = n - 3 ; i >= 0 ; i--){ if(main[0][i + 1] == '>'){ dp[0][i] = dp[0][i + 2] ; } if((dp[0][i] == -1 || dp[0][i] == 0) && main[1][i] == '>') dp[0][i] = dp[1][i + 1] ; if(dp[0][i] != 1){ dp[0][i] = 0 ; } if(main[1][i + 1] == '>') dp[1][i] = dp[1][i + 2] ; if((dp[1][i] == -1 || dp[1][i] == 0) && main[0][i] == '>') dp[1][i] = dp[0][i + 1] ; if(dp[1][i] != 1) dp[1][i] = 0 ; } if(dp[0][0] == 1) cout

[@ChiragWadwa]

dude your testcase is invalid , n is even

[@prime_great]

​​@@ChiragWadwa Ok I understand that part ... But I want to say that I am not checking that either (2 , n -2) is > .. then also mine code is working And also that it is not necessary that we should reach 2 , n by after second step only ... That is if we reach 2 , n by after first step only then also and must be yes.. It is like robot just want to touch that position of 2 , n

[@sangamverma2042]

C. ques [ > > < ][ > < < ] robot move (1,1) -> (1,2) -> (1,3) -> (2,3) finally reached but at (2,2) is '

[@AbhinavAwasthi]

How you are taking only 3 steps, there should be even steps, own step+cell step always taken as group, so after reaching 2,3 it will take own step and each 2,2

[@_u_ya-dw6vx]

@@AbhinavAwasthi sir, i am having the same doubt for the case: [ > < < ] [ > < < ] , this will output NO if I run your code, but it should be yes as we already reached the final state even though the cell step is not taken.. could you please clarify?

[@Beingamanforever]

in that robot question it might also happen that ki, the robot is present above (2,n) and then it takes its own step to go down and reach the final cell, how did we conclude that the last step would be by cell>?

[@AbhinavAwasthi]

If he will take own step to go down, he have to also take cell step, he can't skip, that will make him again on the left of destination

[@Beingamanforever]

@@AbhinavAwasthi understood sir, thank you, also sir can we ask doubts in the telegram channel?

[@Nishkarsh-gc5yr]

for C, can't we just do this, so we first check the initial 0 and n-1 index conditions, keep a variable cnt=0, and then iterate from the 1st and 2nd column and further like this pairwise, (1,2 -> 3,4 -> ... x,x+1 .. -> n-2, n-1), , and check if the odd index of first row is

[@AbhinavAwasthi]

Have you tried this approach?

[@AbjSir]

I was able to do A,B,C in 58mins. Thanks sir

[@AbhinavAwasthi]

Welcome

[@shreyanshsinghal800]

very good approach in the c ques

[@AbhinavAwasthi]

Thanks

[@priyanshuhbtu]

Nice Explanation ..I was only able to solve A,B 🥲

[@AbhinavAwasthi]

Thanks, keep trying 🙌🏻

[@gourabsarkar1706]

thank you for Your Editorials ❤❤ and can you share how to make template like yours

[@AbhinavAwasthi]

Thanks, sure will make

[@jagan5785]

in problem c, robot could have reached 0,n-1 by arrow(>) of 0,n-2 and from 0,n-1 it may reach to 1,n-1 by it's own step(move 1) isn't this a possibility

[@AbhinavAwasthi]

After own step he must take cell step also

[@jagan5785]

we have to reach 1,n-1 after 2 given steps ? @@AbhinavAwasthi

[@AbjSir]

sir you can use x=1-x; instead of x=(x+1)%2; I always use x=1-x; it's easier to write

[@AbhinavAwasthi]

Yes, great

[@rajonhassan8343]

great brother

[@preetu391]

great editorials 🙌

[@AbhinavAwasthi]

Thanks

[@treasurehunter449]

Great explanation for d problem

[@AbhinavAwasthi]

Thanks

[@nikhilsihare1887]

i get the idea of D but not C 😢😢😢😢😢😢😢😢😢😢😢😢😢😢

[@AbhinavAwasthi]

Keep trying 🙌🏻

[@kashishchawla2754]

gr8

[@AbhinavAwasthi]

Thanks

[@pialhasan4550]

sir give proper roadmap ... i am solve olny a pial5566 this in my codeforce id

[@AbhinavAwasthi]

Sure, share will review when free

[@RajGupta-cu9hi]

Devin

[@AbhinavAwasthi]

Ha haa

[@relaxingnaturalvibrations1171]

I don't know why this brute force solution works in problem D. // !! om namah bhagwate vasudevay !! #include using namespace std; int main(){ int t; cin>>t; while(t--){ string s;cin>>s; int n=s.length(); int n1=n; if(n%2==1){ n1=n-1; } int ans=0; for(int i=2;i

[@santoshvocals4781]

Mee seeing the video without solving even one question🥹

[@AbhinavAwasthi]

Keep trying

[@santoshvocals4781]

@@AbhinavAwasthi sure following ur videos I am a newbie will start

[@Cpp_For_Life]

​@@santoshvocals4781what's ur contest rating brother?