Letter Combinations of a Phone Number Dynamic Programming | Mobile Numeric Keypad Problem

Please consume this content on nados.pepcoding.com for a richer experience. It is necessary to solve the questions while watching videos, nados.pepcoding.com enables that.
NADOS also enables doubt support, career opportunities and contests besides free of charge content for learning. Here you will learn about Mobile numeric keypad problem. In this question :
1. You are given a number N, which represents the count of buttons pressed on a mobile numeric keypad.
2. You can only press buttons that are up, left, right, down to the current button and the current button also.
3. You can not press bottom row corner buttons(* and #).
For a better experience and more exercises, VISIT: www.pepcoding....
Have a look at our result: www.pepcoding....
Follow us on our FB page: / pepcoding
Follow us on Instagram: / pepcoding
Follow us on LinkedIn: / pepcoding-education

[@sujoyseal195]

Sir, in the 2 nd iteration , value for 9 should be 3 . Numbers are: 69,89,99 . Which makes it 1+1+1=3. Notice that 7 and 9 are symmetric , so Val(7) = Val(9) must happen. Sir, please clarify. Your explanation is the best, sir

[@shreeyagupta8472]

Also, iteration of N=3 is to be changed accordingly.

[@its_me3716]

you are really doing great work..no other content is such clearly explained..thank you so much

[@lovleshbhatt7797]

for digit 9 the when we consider 2 digits the ans should be 3, Please correct it Thanks for this video.

[@sujoyseal195]

Yes man : 69,89,99

[@rohitshinde8478]

Thank you sir , for this wonderful explaination

[@alesblaze7671]

Bhai you nicely explained it , loved it.

[@Pepcoding]

Thankyou, I am glad you liked it. I also hope that you are watching till end. Will you like to write a few words about us here (www.quora.com/What-are-the-good-websites-to-learn-data-structures-and-algorithms)

[@alesblaze7671]

@@Pepcoding brother although you could have optimised it to use 2 rows only as to calculate current row we need just one previous row. And i will give a good feedback about you on that quora link.

[@Pepcoding]

@@alesblaze7671 agreed, 2 rows mei ho jata

[@PankajKP]

Sir please ek video gas station problem pe bnao vo bhot confusing hai

[@paryt7696]

bhai aap keh rhe ho 1 kiske baad daba ho sakta hai, arey yr ese hi keh do 1 ke baad ye ye daba sakte hai, ya isme koi issue hai?

[@ShrutiAgrahari0803]

best explanation sir

[@Pepcoding]

Glad you liked it! Keep learning. And for better experience, visit nados.io, where you will get well curated content and career opportunities.

[@adityaraghav8693]

this one was a great problem 💥

[@payalsagar1808]

Just wow😍

[@Pepcoding]

Thankyou beta! I am glad you liked it. If you like our efforts, will you like to write a few words about us here (www.quora.com/What-are-the-good-websites-to-learn-data-structures-and-algorithms )

[@Elon-musk-007]

Sirji space complexity can be optimized!

[@factswithai2]

East or west summet sir is the best

[@Pepcoding]

Keep learning, Keep growing and keep loving Pepcoding!😊

[@mukultaneja7243]

Sir.............I think the question is not explained properly on the site. Please rephrase it.

[@Pepcoding]

Alright. I will check

[@sommayghosh4617]

@@Pepcoding acha explanation h sir good work, meine code wala part dekha b ni kyuki algo hi itne ache se smjha dia apne

[@brijpatel237]

Roadies salute :-P !!

[@Pepcoding]

Haha..thankyou! If you like our efforts, will you like to write a few words about us here (www.quora.com/What-are-the-good-websites-to-learn-data-structures-and-algorithms )

[@tusharnain6652]

//Constant Space Solution { // making the data graph for each number vector dataGraph{ {0, 8}, {1, 2, 4}, {1, 2, 3, 5}, {2, 3, 6}, {1, 4, 5, 7}, {2, 4, 5, 6, 8}, {3, 5, 6, 9}, {4, 7, 8}, {5, 7, 8, 9, 0}, {6, 8, 9}}; vector dp(10); for (int i = 0; i < 10; i++) dp[i] = 1; for (int i = 2; i

[@pulkitgupta9441]

This is a little different approach to the same logic import java.io.*; import java.util.*; public class Main { public static boolean isValid(int i, int j) { if(i >= 0 && j >= 0 && i < 4 && j < 3) return true; else return false; } public static int solution(int n) { int[][] curr = new int[4][3]; int[][] next = new int[4][3]; for(int i = 0; i < curr.length ; i++) { for(int j = 0; j < curr[0].length; j++) { curr[i][j] = 1; } } curr[3][0] = 0; curr[3][2] = 0; for(int l = 2; l

[@abhisheksadhu411]

Sir, great explanation..... ☺ I have put up query, pls reply me on telegram sir....