867. Transpose Matrix - 데일리 문제

867. Transpose Matrix

난이도: Easy

---

Given a 2D integer array matrix, return the transpose of matrix.

The transpose of a matrix is the matrix flipped over its main diagonal, switching the matrix's row and column indices.

 

Example 1:

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

Example 2:

Input: matrix = [[1,2,3],[4,5,6]]
Output: [[1,4],[2,5],[3,6]]

 

Constraints:

• m == matrix.length
• n == matrix[i].length
• 1 <= m, n <= 1000
• 1 <= m * n <= 105
• -109 <= matrix[i][j] <= 109

 

문제 설명

전치 행렬을 구하는 문제로 단순하게 행과 열을 바꿔주면 된다. 

 

코드

/**
 * @param {number[][]} matrix
 * @return {number[][]}
 */
var transpose = function(matrix) {
    const res =[]
    for(let i=0; i<matrix[0].length; i++){
        const tmp = []
        for(let j=0; j<matrix.length; j++){
            tmp.push(matrix[j][i])
        }
        res.push(tmp)
    }
    return res
};