add unique-paths

Author: i-mprovising

unique-paths/i-mprovising.py

@@ -0,0 +1,21 @@
+"""
+Time, space complexity O(m*n)
+
+Dynamic programming
+"""
+
+class Solution:
+    def uniquePaths(self, m: int, n: int) -> int:
+        dp = [[0 for _ in range(n)] for _ in range(m)]
+        dp[0] = [1 for _ in range(n)]
+
+        for i in range(1, m):
+            for j in range(n):
+                if i == 0:
+                    continue
+                if j == 0:
+                    dp[i][j] = 1
+                    continue
+                dp[i][j] = dp[i-1][j] + dp[i][j-1]
+        
+        return dp[-1][-1]