Add 64_Minimum_Path_Sum.java

Matrix/64_Minimum_Path_Sum.java

@@ -0,0 +1,33 @@
+class Solution {
+    public int minPathSum(int[][] grid) {
+        int height = grid.length, width = grid[0].length;
+        int[][] memo = new int[height][width];
+
+        for (int[] row : memo) {
+            Arrays.fill(row, -1);
+        }
+
+        return helper(grid, 0, 0, memo);
+    }
+
+    private int helper(int[][] grid, int row, int col, int[][] memo) {
+        if (row == grid.length - 1 && col == grid[0].length - 1) {
+            return grid[row][col];
+        }
+
+        if (memo[row][col] != -1) {
+            return memo[row][col];
+        }
+
+        if (row == grid.length - 1) {
+            return grid[row][col] + helper(grid, row, col + 1, memo);
+        }
+        if (col == grid[0].length - 1) {
+            return grid[row][col] + helper(grid, row + 1, col, memo);
+        }
+
+        int result = grid[row][col] + Math.min(helper(grid, row + 1, col, memo), helper(grid, row, col + 1, memo));
+        memo[row][col] = result;
+        return result;
+    }
+}