leetcode 48. Rotate Image

反转一个图片

需要认真观察其规律

/*
    [0, 0] -> [0, 3] 
    [0, 1] -> [1, 3]
    [1, 0] -> [0, 2]//4-1-1
    [i, j] -> [j, n-i -1]//4-0-1
*/
var rotate = function(matrix) {
    var n = matrix.length;
    var m = matrix[0].length;
    var clone = JSON.parse(JSON.stringify(matrix))
    for(var i = 0; i < n; i ++){
        for(var j= 0; j < m; j++){
            matrix[j][n-i-1] = clone[i][j] 
        }
    }
    
};