Leetcode 62

Python Solution

Author: kyle8998

Diff for: README.md

@@ -47,6 +47,7 @@ Personal Practice Set - Doing One a Day (sometimes) in a Variety of Languages (M
 | 54 | Medium     | [Spiral Matrix](leetcode/54-Medium-Spiral-Matrix/problem.md)                                 | [Python](leetcode/54-Medium-Spiral-Matrix/answer.py)              |
 | 56 | Medium     | [Merge Intervals](leetcode/56-Medium-Merge-Intervals/problem.md)                             | [Python](leetcode/56-Medium-Merge-Intervals/answer.py)            |
 | 58 | Easy       | [Length of Last Word](leetcode/58-Easy-Length-Of-Last-Word/problem.md)                       | [Python](leetcode/58-Easy-Length-Of-Last-Word/answer.py)          |
+| 62 | Medium     | [Unique Paths](leetcode/62-Medium-Unique-Paths/problem.md)                                   | [Python](leetcode/62-Medium-Unique-Paths/answer.py)               |
 | 66 | Easy       | [Plus One](leetcode/66-Easy-Plus-One/problem.md)                                             | [Python](leetcode/66-Easy-Plus-One/answer.py)                     |
 | 67 | Easy       | [Add Binary](leetcode/67-Easy-Add-Binary/problem.md)                                         | [Python](leetcode/67-Easy-Add-Binary/answer.py)                   |
 | 69 | Easy       | [Sqrt()](leetcode/69-Easy-Sqrt/problem.md)                                                   | [Python](leetcode/69-Easy-Sqrt/answer.py)                         |

Diff for: leetcode/62-Medium-Unique-Paths/answer.py

@@ -0,0 +1,27 @@
+#!/usr/bin/python3
+
+#------------------------------------------------------------------------------
+
+class Solution:
+    def uniquePaths(self, m, n):
+        """
+        :type m: int
+        :type n: int
+        :rtype: int
+        """
+        # Create the grid to keep track of paths
+        grid = [[0]*n for _ in range(m)]
+        # Iterate through each path
+        for i in range(m):
+            for j in range(n):
+                # If start (i==0 or j==0) set to 1
+                if not i or not j:
+                    grid[i][j] = 1
+                else:
+                    # Sum up the possible paths reaching this spot
+                    grid[i][j] = grid[i-1][j] + grid[i][j-1]
+        return grid[m-1][n-1]
+        
+
+#------------------------------------------------------------------------------
+#Testing

Diff for: leetcode/62-Medium-Unique-Paths/problem.md

@@ -0,0 +1,32 @@
+# Problem 62: Unique Paths
+
+
+#### Difficulty: Medium
+
+#### Problem
+
+A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).
+
+The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).
+
+How many possible unique paths are there?
+
+#### Example
+
+<pre>
+
+Input: m = 3, n = 2
+Output: 3
+
+Explanation:
+
+From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:
+
+1. Right -> Right -> Down
+
+2. Right -> Down -> Right
+
+3. Down -> Right -> Right
+
+</pre>
+