Transpose of a Matrix - Amazon Top Interview Questions

Problem Statement :

Given an integer square (n by n) matrix, return its transpose. A transpose of a matrix switches the row and column indices. That is, for every r and c, matrix[r][c] = matrix[c][r].


n ≤ 100

Example 1


matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]

    [1, 4, 7],
    [2, 5, 8],
    [3, 6, 9]

Solution :


                        Solution in C++ :

vector<vector<int>> solve(vector<vector<int>>& nums) {
    vector<vector<int>> v(nums.size(), vector<int>(nums.size()));
    for (int i = 0; i < nums.size(); i++) {
        for (int j = 0; j < nums.size(); j++) {
            v[i][j] = nums[j][i];
    return v;

                        Solution in Java :

import java.util.*;

class Solution {
    public int[][] solve(int[][] matrix) {
        if (matrix.length == 0)
            return new int[0][0];
        int length = matrix[0].length;

        for (int i = 0; i < length; i++) {
            for (int j = i + 1; j < length; j++) {
                int temp = matrix[i][j];
                matrix[i][j] = matrix[j][i];
                matrix[j][i] = temp;
        return matrix;

                        Solution in Python : 
class Solution:
    def solve(self, matrix):
        for row in range(len(matrix)):
            for col in range(len(matrix[0])):
                if row < col:
                    matrix[row][col], matrix[col][row] = matrix[col][row], matrix[row][col]
        return matrix

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