Recently attended Cisco (company name) The overall experience of SDE Intern OA is that the questions are not particularly difficult, but the time is very tight. 90 minutes for three questions and you will easily be unable to finish. Cisco's OA emphasizes whether you can quickly grasp the essence, rather than wasting time in brute force. Here to organize the questions and ideas, I hope to help students who are preparing.
Cisco SDE Intern OA Interview overview
- Question volume: 3 programming questions
- Duration:90 minutes
- Distribution of Examination Points:
- Matrix operations (looking at space/time optimization)
- String Handling (palindrome high-frequency exams + dictionary order rules)
- HashMap Applications (Frequency Statistics and Abstract Modeling)
Overall difficulty: moderate to high. The key is to recognize patterns and write efficient solutions.
Cisco SDE Intern OA Real Questions Sharing + Thoughts
1. Matrix Rotation Print
Question.
Given an N × M matrix, rotate it 90 degrees clockwise and print it row by row.
Naive approach.
- Create a new M × N matrix.
- For each element
matrix[i][j], place it intorotated[j][N - 1 - i]. - Finally, print row by row.
- Complexity: O(NM) time, O(NM) space.
Optimized approach.
- Notice you don't actually need to build a rotated matrix.
- For a clockwise 90° rotation, the first row of the result corresponds to the last column of the original matrix.
- Instead of allocating extra space, iterate over the original matrix column by column (left → right), printing each column in reverse (bottom → top).
- Complexity: O(NM) time, O(1) space.
2. Longest Palindromic Substring
Question.
Given a string, return the longest palindromic substring. If multiple substrings have the same maximum length, return the lexicographically smallest one.
Approach 1 (Expand Around Center).
- For each index, expand outward for both odd-length and even-length palindromes.
- Keep track of the longest palindrome found.
- If two palindromes have the same length, compare and keep the lexicographically smaller one.
- Complexity: O(N²) time, O(1) space.
Approach 2 (Dynamic Programming).
- Use a DP table
dp[i][j] = trueif substrings[i... .j]is a palindrome. - Fill table bottom-up and track the longest palindrome.
- Lexicographical comparison needed when length ties occur.
- Complexity: O(N²) time and space.
3. Maximum Coordinates in One Flight
Question.
Given a list of coordinate pairs (x, y). You can "fly" either horizontally (same y) or vertically (same x), but only once. Find the maximum number of coordinates you Find the maximum number of coordinates you can pass through.
Approach.
- The problem reduces to.
- Count how many points share the same x-coordinate.
- Count how many points share the same y-coordinate.
- Use two HashMaps.
x_count[x]++For every point.y_count[y]++For every point.
- The answer is
max(max(x_count.values()), max(y_count.values())). - Complexity: O(N) time, O(N) space.
The secret to a solid Offer
Cisco's OA is particularly fast-paced, and there are so many topics that if you keep writing slowly with brute force, you simply won't have enough time.Programhelp Through the OA untraceable on-line assistance, in advance to take you to rehearse Cisco high-frequency question types (matrix optimization, echo, HashMap statistics), the real on the field can also voice reminder of you in time to change the idea, will not be trapped in the inefficient solution. Like Cisco, Amazon, Akuna such high-pressure OA, want to get a high score steadily, rely on their own hard support is far from enough, advance rehearsal + practical assistance is the king.
