Create 0064-minimum-path-sum.kt

Author: a93a

Diff for: kotlin/0064-minimum-path-sum.kt

@@ -0,0 +1,22 @@
+class Solution {
+    fun minPathSum(grid: Array<IntArray>): Int {
+        val m = grid.lastIndex
+        val n = grid[0].lastIndex
+        
+        for(i in m - 1 downTo 0) {
+            grid[i][n] += grid[i + 1][n]
+        }
+
+        for(j in n - 1 downTo 0) {
+            grid[m][j] += grid[m][j + 1]
+        }
+
+        for(i in grid.lastIndex - 1 downTo 0) {
+            for(j in grid[0].lastIndex - 1 downTo 0) {
+                grid[i][j] += minOf(grid[i + 1][j], grid[i][j + 1])
+            }
+        }
+
+        return grid[0][0]
+    }
+}