refactor 304

fishercoder1534 · fishercoder1534 · commit aeb4bcba68a7 · 2018-12-11T07:58:06.000-08:00
diff --git a/src/main/java/com/fishercoder/solutions/_304.java b/src/main/java/com/fishercoder/solutions/_304.java
@@ -1,6 +1,8 @@
 package com.fishercoder.solutions;
 
 /**
+ * 304. Range Sum Query 2D - Immutable
+ *
  * Given a 2D matrix matrix, find the sum of the elements inside the rectangle defined by its upper left corner (row1, col1) and lower right corner (row2, col2).
 
  Range Sum Query 2D
@@ -25,30 +27,32 @@ The above rectangle (with the red border) is defined by (row1, col1) = (2, 1) an
  */
 public class _304 {
 
-    public class NumMatrix {
+    public static class Solution1 {
+        public class NumMatrix {
 
-        public NumMatrix(int[][] matrix) {
-            if (matrix == null || matrix.length == 0 || matrix[0].length == 0) {
-                return;
-            }
+            public NumMatrix(int[][] matrix) {
+                if (matrix == null || matrix.length == 0 || matrix[0].length == 0) {
+                    return;
+                }
 
-            /**The dimensions of this tot matrix is actually 1 bigger than the given matrix, cool!*/
-            tot = new int[matrix.length + 1][matrix[0].length + 1];
-            for (int i = 0; i < matrix.length; i++) {
-                for (int j = 0; j < matrix[0].length; j++) {
-                    tot[i + 1][j + 1] = matrix[i][j] + tot[i + 1][j] + tot[i][j + 1] - tot[i][j];
+                /**The dimensions of this tot matrix is actually 1 bigger than the given matrix, cool!*/
+                tot = new int[matrix.length + 1][matrix[0].length + 1];
+                for (int i = 0; i < matrix.length; i++) {
+                    for (int j = 0; j < matrix[0].length; j++) {
+                        tot[i + 1][j + 1] =
+                            matrix[i][j] + tot[i + 1][j] + tot[i][j + 1] - tot[i][j];
+                    }
                 }
             }
-        }
 
-        public int sumRegion(int row1, int col1, int row2, int col2) {
-            return tot[row2 + 1][col2 + 1] - tot[row2 + 1][col1] - tot[row1][col2 + 1]
+            public int sumRegion(int row1, int col1, int row2, int col2) {
+                return tot[row2 + 1][col2 + 1] - tot[row2 + 1][col1] - tot[row1][col2 + 1]
                     + tot[row1][col1];
-        }
+            }
 
-        int[][] tot;
+            int[][] tot;
+        }
     }
-
 /**
  * Your NumMatrix object will be instantiated and called as such:
  * NumMatrix obj = new NumMatrix(matrix);
