# Post Only Coding Problems & Solutions Here | All Coding Guru's Dig In **URL:** \ **Category:** Discussion & Solutions\ **Tags:** business\ **Created:** [October 20, 2019, 9:23am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680 "2019-10-20T09:23:31Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Summer\_Jance](https://onehack.st/user_avatar/onehack.st/summer_jance/32/19952_2.png) [@Summer\_Jance](https://onehack.st/u/Summer_Jance)\ **Post date:** [October 27, 2019, 10:25am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/45 "2019-10-27T10:25:25Z")
primarily can think of 2 ways to solve the above combination problem. using for loop and recursion. prefer loop as i’m not sure you’re language supports tail call optimization for i → 0 to len(str) comb = ithStr print(comb)   for j → i+1 to len(str)     comb = comb + jthStr     print(comb)  end forj end fori **Note** ```auto comb = comb + jthStr ``` in some language + can be used for combining string. Some don’t you can use you’re language specific / write a general function todo so ---
**Author:** ![nikhilknick](https://onehack.st/user_avatar/onehack.st/nikhilknick/32/22060_2.png) [@nikhilknick](https://onehack.st/u/nikhilknick)\ **Post date:** [November 2, 2019, 8:40pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/65 "2019-11-02T20:40:57Z")
Solution to problem 8 code in javascript ``` const outsub = (str) => { for(var i=0;i<=str.length;i++){ for(var j=0;j<=str.length-i;j++){ console.log(str.substr(i,j)); } } } outsub('abcd'); ``` ---
**Author:** ![Darklooter](https://onehack.st/user_avatar/onehack.st/darklooter/32/1882_2.png) [@Darklooter](https://onehack.st/u/Darklooter)\ **Post date:** [October 27, 2019, 11:35pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/47 "2019-10-27T23:35:49Z")
I have to learn maps , I guess any problem can b solved by this.😂😂🤪 ---
**Author:** ![goku\_pistol](https://onehack.st/user_avatar/onehack.st/goku_pistol/32/24327_2.png) [@goku\_pistol](https://onehack.st/u/goku_pistol)\ **Post date:** [October 28, 2019, 5:25am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/48 "2019-10-28T05:25:18Z")
You should!! map(),filter(), reduce() and zip() are really useful. Btw, I have only used it for taking inputs in single line and type cast string to integer i.e. same as “cin \>\> a \>\> b \>\> c” in C++ 😅 ---
**Author:** ![Ak\_Malviya](https://onehack.st/user_avatar/onehack.st/ak_malviya/32/23188_2.png) [@Ak\_Malviya](https://onehack.st/u/Ak_Malviya)\ **Post date:** [October 28, 2019, 7:39am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/49 "2019-10-28T07:39:08Z")
**Problem Number 8 Solution:** ``` #include #include #include using namespace std; int main() { string str; cin>>str; int i=0,j=0,k=0; int size_str=str.length(); while(i < size_str) { j=0; while(j **Author:** ![Ak\_Malviya](https://onehack.st/user_avatar/onehack.st/ak_malviya/32/23188_2.png) [@Ak\_Malviya](https://onehack.st/u/Ak_Malviya)\ **Post date:** [October 28, 2019, 11:41am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/50 "2019-10-28T11:41:10Z") **Problem 9:** You are given an array of nonnegative integers. Let’s say you start at the beginning of the array and are trying to advance to the end. You can advance at most, the number of steps that you’re currently on. Determine whether you can get to the end of the array. For example, given the array `[1, 3, 1, 2, 0, 1]` , we can go from indices `0 -> 1 -> 3 -> 5` , so return `true` . Given the array `[1, 2, 1, 0, 0]` , we can’t reach the end, so return `false` . ---
**Author:** ![Darklooter](https://onehack.st/user_avatar/onehack.st/darklooter/32/1882_2.png) [@Darklooter](https://onehack.st/u/Darklooter)\ **Post date:** [October 28, 2019, 3:13pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/54 "2019-10-28T15:13:04Z")
the statement seems a little confusing can you tell me the source of this question? ---
**Author:** ![Ak\_Malviya](https://onehack.st/user_avatar/onehack.st/ak_malviya/32/23188_2.png) [@Ak\_Malviya](https://onehack.st/u/Ak_Malviya)\ **Post date:** [October 28, 2019, 3:17pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/55 "2019-10-28T15:17:30Z")
Daily Coding Problem, It is asked by **google**. ---
**Author:** ![Darklooter](https://onehack.st/user_avatar/onehack.st/darklooter/32/1882_2.png) [@Darklooter](https://onehack.st/u/Darklooter)\ **Post date:** [October 28, 2019, 5:13pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/56 "2019-10-28T17:13:27Z")
Is that the exact statement ? ---
**Author:** ![Ak\_Malviya](https://onehack.st/user_avatar/onehack.st/ak_malviya/32/23188_2.png) [@Ak\_Malviya](https://onehack.st/u/Ak_Malviya)\ **Post date:** [October 28, 2019, 5:25pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/57 "2019-10-28T17:25:36Z")
Yes, this is the exact statement. This problem can be solved by dynamic programming technique. ---
**Author:** ![Magnus](https://onehack.st/user_avatar/onehack.st/magnus/32/26177_2.png) [@Magnus](https://onehack.st/u/Magnus)\ **Post date:** [October 29, 2019, 1:58pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/58 "2019-10-29T13:58:28Z")
I wrote a solution but I’m not 100% sure I understood the problem (bad practice I know :p) what I understood: we start from the first index, and the next index we jump to is currentindex+the value in that current index. we keep doing this until either: - we get to the end - we go out of bound - the value we get to is zero (we can’t go forward anymore). Based on that explanation, here is the function that does the job, in c++: ``` bool reachesEnd(int arr[] ,const int arrSize, int currentIndex){ if(currentIndex==arrSize-1) return 1; if(currentIndex>=arrSize) return 0; if(arr[currentIndex]==0) return 0; return reachesEnd(arr , arrSize , currentIndex+arr[currentIndex]); } ``` Please inform me if I understood the problem correctly. ---
**Author:** ![Ak\_Malviya](https://onehack.st/user_avatar/onehack.st/ak_malviya/32/23188_2.png) [@Ak\_Malviya](https://onehack.st/u/Ak_Malviya)\ **Post date:** [October 29, 2019, 5:24pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/59 "2019-10-29T17:24:03Z")
Yes, you understood the problem correctly. ---
**Author:** ![Mayank](https://onehack.st/user_avatar/onehack.st/mayank/32/18032_2.png) [@Mayank](https://onehack.st/u/Mayank)\ **Post date:** [November 2, 2019, 5:04pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/61 "2019-11-02T17:04:16Z")
for Problem 9: Each state defines number of jumps can be made from one node to other. for example state `5` , represent jumps at max `5` and at min `0` and to solve you must reach the end of the node. _Assumption_ 1. All states are whole number. _edge cases_ 1. If the current node is the last node. 2. if all the nodes state are `0`. 3. if node is not end\_indx and value is `0`. Pseudocode for **top down approach** : ```auto func jump_resolver(arr,curr_indx) if curr_indx is end_indx (reached end ) return true; end if if curr_indx past end_indx (greater than end_indx) return false end if state_val = arr[curr_indx] if state_val == 0 // no increment we stop here return false; for i=state_val to 1 do reached = jump_resolver(arr,curr_indx+i); if reached return true; end for return false; // as we tried all the jumps ``` Pseudocode for **bottom up approach** : a. using stack iterativerly > stack initalized with {fnstate:‘CALL’,ctxt:{indx:0} ```auto dest = false // is end reached while stack.hasElements() fnstate,ctxt= stk.pop() // here pop and get what is the current function state and context if fnstate == 'CALL' if curr_indx past end_indx (greater than end_indx) dest = false continue; // moves to start of while end if if ctxt.indx == end_indx dest = true; else // inner else val = arr[ctxt.indx]; // fetch the value from current index of arr if val == 0 dest = false // if it's not nth index and it's value is 0 , return false continue; // move forward with while loop end if push to stk {fnstate:'RES',ctxt:{indx:ctxt.indx} // later we will resume at context index for i = val to 1 do push to stk {fnstate:'CALL',ctxt:{indx:ctxt.indx+i} if dest // on destination reach break; end for // end inner for end while // outer while ``` **Note** 1. There is even better way to do this via disjoint set. 2. using memoization for recursion would be better. ---
**Author:** ![Mayank](https://onehack.st/user_avatar/onehack.st/mayank/32/18032_2.png) [@Mayank](https://onehack.st/u/Mayank)\ **Post date:** [November 3, 2019, 11:01pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/68 "2019-11-03T23:01:04Z")
> [@Ak\_Malviya](#): > > Yes, this is the exact statement. This problem can be solved by dynamic programming technique. The problem can be solved **by recursion [for better use DP , to avoid TLE]**. Is that what you meant? ---
**Author:** ![Mahammedi\_Zakaria](https://onehack.st/user_avatar/onehack.st/mahammedi_zakaria/32/20622_2.png) [@Mahammedi\_Zakaria](https://onehack.st/u/Mahammedi_Zakaria)\ **Post date:** [October 28, 2019, 11:54am UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/52 "2019-10-28T11:54:08Z")
hello guys i have a quick simple question , i want to code a food app that have an integrated delivery tracking system and chat what am i going to need ? ---
**Author:** ![Darklooter](https://onehack.st/user_avatar/onehack.st/darklooter/32/1882_2.png) [@Darklooter](https://onehack.st/u/Darklooter)\ **Post date:** [October 28, 2019, 12:37pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/53 "2019-10-28T12:37:54Z")
A computer Decide a tech stack Firebase (Search youtube for reference ) ---
**Author:** ![Darklooter](https://onehack.st/user_avatar/onehack.st/darklooter/32/1882_2.png) [@Darklooter](https://onehack.st/u/Darklooter)\ **Post date:** [October 31, 2019, 5:15pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/60 "2019-10-31T17:15:19Z")
**Problem 10** GIven a string like **java is good but javascript is awesome** sort this string on the basis of number of vowels it has. so the output will be **is but is java good javascript awesome** ---
**Author:** ![Mayank](https://onehack.st/user_avatar/onehack.st/mayank/32/18032_2.png) [@Mayank](https://onehack.st/u/Mayank)\ **Post date:** [November 2, 2019, 5:48pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/62 "2019-11-02T17:48:49Z")
theory fetch string , convert to array of strings assign each string a value based on number of vowels sort it and display. pseudocode ```auto func display() vals[] // array of vals after split(" ") use treeMap (modify how elements are compared , here elements are string with help of spit_vowl_count) as you keep adding str to tree , it sorts and adds the element for val to treeMap console val + ' ' end for // you can use iterator pattern if you want end func func spit_vowl_count(str) sum = 0 for i 0 to len(str) if str(i) belongs to `a` , `e`, `i`, `o`, `u` sum + = 1; end for return sum end func ``` ---
**Author:** ![nikhilknick](https://onehack.st/user_avatar/onehack.st/nikhilknick/32/22060_2.png) [@nikhilknick](https://onehack.st/u/nikhilknick)\ **Post date:** [November 2, 2019, 8:36pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/64 "2019-11-02T20:36:28Z")
My solution to Problem 10 Code in Javascript ``` //function to count vowel of each item const countVowels = (s)=> { let vowels = 'aeiouAEIOU'; let count = 0; for(let i = 0; i < s.length ; i++) if (vowels.indexOf(s[i]) !== -1) count += 1; return count; } //function to sort accoring to the no of vowels const vowelSort = (str) => { let s = str.split(' ').sort((a,b)=>{ let countA = countVowels(a); let countB = countVowels(b); if (countA < countB) return -1; if (countA > countB) return 1; }) return s.join(' '); //returning the final output } vowelSort('java is good but javascript is awesome'); ``` ---
**Author:** ![nikhilknick](https://onehack.st/user_avatar/onehack.st/nikhilknick/32/22060_2.png) [@nikhilknick](https://onehack.st/u/nikhilknick)\ **Post date:** [November 2, 2019, 8:55pm UTC](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680/66 "2019-11-02T20:55:25Z")
**Problem 11** Write a function persistence that takes in a positive parameter num and returns its multiplicative persistence, which is the number of times you must multiply the digits in num until you reach a single digit. For example: persistence(39) === 3 // because 3_9 = 27, 2_7 = 14, 1_4= 4 and 4 has only one digit persistence(999) === 4 // because 9_9_9 = 729, 7_2_9 = 126, 1_2_6 = 12, and finally 1_2 = 2 persistence(4) === 0 // because 4 is already a one-digit number [Previous page](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680.md?page=2) [Next page](https://onehack.st/t/post-only-coding-problems-solutions-here-all-coding-gurus-dig-in/60680.md?page=4)