Merge pull request chihungyu1116#4 from ignacio-chiazzo/rotate-image

clearer solution rotate image

Author: ignacio-chiazzo

48 Rotate Image.js

@@ -11,20 +11,20 @@
  */
 var rotate = function(matrix) {
     var row = matrix.length;
-    
+
     if(row === 0) {
         return;
     }
-    
+
     var col = matrix[0].length;
-    
+
     // swap them in diagonal
     for(var i = 0; i < row; i++) {
         for(var j = 0; j < col - i; j++) {
             swap(matrix, i, j, row - 1 - j, col  - 1 - i);
         }
     }
-    
+
     // swap in middle
     for(i = 0; i < Math.floor(row/2); i++) {
         for(j = 0; j < col; j++) {
@@ -37,4 +37,37 @@ function swap(matrix, x1, y1, x2, y2) {
     var tmp = matrix[x1][y1];
     matrix[x1][y1] = matrix[x2][y2];
     matrix[x2][y2] = tmp;
-}
+}
+
+//Clearer Solution
+var rotate = function(matrix) {
+    rotateColumns(matrix);
+    rotateEachDiagonal(matrix);
+};
+
+var rotateColumns = function(matrix) {
+    for(var j = 0; j < matrix.length; j++) {
+        var low = 0;
+        var ceil = matrix.length -1;
+        while(low < ceil) {
+            swap(matrix, low, j, ceil, j);
+            low++;
+            ceil--;
+        }
+    }
+};
+
+var rotateEachDiagonal = function(matrix){
+    for(var i = 0; i < matrix.length; i++) {
+        for(var j = i; j < matrix.length; j++) {
+            swap(matrix, i, j, j, i);
+        }
+    }
+};
+
+var swap = function(matrix, i1, j1, i2, j2) {
+    var aux = matrix[i1][j1];
+    matrix[i1][j1] = matrix[i2][j2];
+    matrix[i2][j2] = aux;
+};
+