solve problem

Author: delight010

unique-paths/delight010.swift

@@ -0,0 +1,13 @@
+class Solution {
+    func uniquePaths(_ m: Int, _ n: Int) -> Int {
+        let column = Array(repeating: 1, count: n)
+        var grid: [[Int]] = Array(repeating: column, count: m)
+        for i in 1..<m {
+            for j in 1..<n {
+                grid[i][j] = grid[i - 1][j] + grid[i][j - 1]
+            }
+        }
+        return grid.last!.last!
+    }
+}
+