# Senior software development engineer Interview Questions in Las Vegas, NV, US

# 991

Senior Software Development Engineer interview questions shared by candidates### 1) Given a array and a sum, find all the pairs in the array which have the given sum. 2) Given a BST you need to identify swapped nodes

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1) Iterate through the list and create a hashmap of an integer to integer where 1st value is the value in the array and second is the repetition (takes O(n) time). Now iterate through this hashmap and for every value (say a), and assume x is the sum map.get(x-a) * map.get(a) but make sure map.get(x-a) is not null or map.get(x-a) != map.get(a) (if it is then apply combinations as a total amount as C(map.get(a), 2) ). You could either count this or print up to the interviewer, and this iteration will take O(n) worst case. So the algorithm will be linear. There are less efficient ways too such as sort the list (n lgn) and then have an initial loop (n) and then apply quick select(lgn) which would make O(n lgn) again so overall complexity would be O(n lgn). Worst one is brute force where you could have two nested loops and compare every value which would take O(n^2) time 2) needs some clarifications such as how do we understand a node is "swapped"? Less

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I exp to call me

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PSEUDO CODE FOR QUESTION ONE THAT SHALL NOT LIST UNIQUE PAIRS BUT SHALL INCLUDE INVERSE PAIRS TOO... Let Array be ARY of 'n' elements and given Sum be SUM. Let the result be RESULT string. Begin. Initialize RESULT string; Let i and j be integer variables; for (initial value of i=0, while i < or = n, increment i by 1) { for ( initial value j = 0, while j < or = n, increment j by 1) { if ((i not equal to j) and ( if (ARY[i] + ARY[j] ) is equal to SUM)) RESULT = RESULT + " ("+ ARY[i] + ","+ ARY[j] +" )" } } Print RESULT; End. Less

### Given a string, konylabsinterview write a program to return bool if a given pattern matches.pattern example - kon*lab*terview*

5 Answers↳

public class Test{ public static void main(String args[]){ String Str = new String("konylabsinterview"); System.out.print("Return Value :" ); System.out.println(Str.matches("kon(.*)lab(.*)terview(.*)")); } } Less

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Use KMP

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Hi, Please see if you can provide the details of the question posed in the context of binary search tree. Thanks. Less

### Give a 2D rectangular array represented as a 1D arrary in row-major form, rotate the array by 90 degrees

4 Answers↳

I came up with a solution where you transpose the array and then exchange the colums. But this is very inefficient. Does anyone have a better solution. Less

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Let n be the number of rows and m be the number of columns. Make m stacks of (n-1) size, Less

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Let n be the number of rows and m be the number of columns. Make m stacks of (n-1) size and iterate through your "2D" array by successively pushing entries through stacks: eg. (entry i is being pushed in stack ~(i mod m)) when i reaches m x (n-1) pop stack and overwrite entries in the "2D" array from the beginning until empty + i'th entry then go to the next stack. Repeat until done. this should run in m x (n-1) + m x n = m x (2n +1) and uses m x (n-1) x (data entry mem size) extra memory during the run. If you want to use less memory, it gets a whole lot more complicated but won't be as quick. Less

### One of the question was on Designing & Code a TTL Cache with some modifications

4 Answers### Probability of a knight making a valid move on NxN matrix in m steps.

4 Answers↳

Buddy, I think you thinking a bit too complicatedly. A knight on a chess board only has 8 legal moves. and if it is anywhere closer than being atleast 2 boxes from the border it will be less than 8. just take a input of all the pieces on the NxN matrix. check these 8 positions and calculate the probability Less

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Given in the description above.

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Guess what , I got almost the same question on my first interview with Google , and I was applying as a new college grad ....i also can up with a DP solution with O(64m) .... btw can you provide the link to the solution you came across ...?? Less

### Write a function that detects the first non-repeating character in a char array, and do so with only a single pass over the array.

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Hhh

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Just use an int arr of size 256 and a queue

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There's quite an extended back and forth in actual interviews for questions like this, so nothing quite like real practice. The Prepfully Zillow Senior Software Development Engineer experts have actually worked in this role, so they're able to do an honest-to-God accurate mock, which really puts you through the paces. prepfully.com/practice-interviews Less

### Write a function/method with this signature: bool MyFunc(string term, string input) {} The method should return true if the search term is found in the input string, even when there are other characters in between. Examples: "aba", "bbbbabbxxxxxxbb" returns false "aba", "bbbbabbxxxxxxab" returns true Basically, do I see an 'a', then 'b', then another 'a' before I run off the end of the input string?

3 Answers↳

static boolean MyFunc(String term, String input) { int j=0; for(int i=0;i Less

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static boolean MyFunc(String term, String input) { int j=0; for(int i=0;i Less

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complexity: computational=O(n) (actually, Theta(n)); disk=O(1). public class MyClass { public static void main(String args[]) { System.out.println("Found = " + myFunc("aba","bbbbbbabbbbbxxxxxab")); System.out.println("Found = " + myFunc("aba","bbbbbbababbbbxxxxxab")); System.out.println("Found = " + myFunc("aba","bbbbbbbbbbabbbbbbbbbbbbbbbaba")); // add @Tests } public static boolean myFunc(String term, String input) { boolean found=false; int j=0,i=0; // Edge cases if(term.length()>input.length()) return false; if(term.length()==0) return true; // O(n): scanning the input while(i Less

### Coding round : If A,B,C are 3 non-zero digits(1-9), find all combinations of A,B,C such that AB * AB = CAB.

3 Answers↳

AB * AB = CAB and not ABC

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Just solve it mathematically by considering all possible digits that satisfy this condition at units digit first and then the solution will automatically fall in place. Less

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If i understood the problem correctly: Repetition is allowed Sol: If you see AB*AB = ABC -> (AB*AB)/AB=C; ->AB = C; so basically you need to find out those values whose multiplication is equal to C and C can not be more than 9: So you will find these : (1,1)(1,2).....(1,9) (2,1)(2,2)(2,3)(2,4), (3,1)(3,2)(3,3),(4,1),(4,2),(5,1)(6,1)(7,1)(8,1)(91) Less