@@ -0,0 +1,794 @@
+package leetcode;%0A%0A/**%0A * https://leetcode.com/problems/range-sum-query-2d-immutable/%0A */%0Apublic class Problem304 %7B%0A    public static class NumMatrix %7B%0A%0A        public NumMatrix(int%5B%5D%5B%5D matrix) %7B%0A%0A        %7D%0A%0A        public int sumRegion(int row1, int col1, int row2, int col2) %7B%0A            // TODO:%0A            return 0;%0A        %7D%0A    %7D%0A%0A    public static void main(String%5B%5D args) %7B%0A        NumMatrix matrix = new NumMatrix(new int%5B%5D%5B%5D%7B%0A            %7B3, 0, 1, 4, 2%7D,%0A            %7B5, 6, 3, 2, 1%7D,%0A            %7B1, 2, 0, 1, 5%7D,%0A            %7B4, 1, 0, 1, 7%7D,%0A            %7B1, 0, 3, 0, 5%7D,%0A        %7D);%0A        System.out.println(matrix.sumRegion(2, 1, 4, 3)); // 8%0A        System.out.println(matrix.sumRegion(1, 1, 2, 2)); // 11%0A        System.out.println(matrix.sumRegion(1, 2, 2, 4)); // 12%0A    %7D%0A%7D%0A

Create a skeleton for problem 304