# Unique Path

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?

Above is a 7 x 3 grid. How many possible unique paths are there?

Example 1:

```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
```

Example 2:

```Input: m = 7, n = 3
Output: 28
```

Constraints:

• `1 <= m, n <= 100`
• It’s guaranteed that the answer will be less than or equal to `2 * 10 ^ 9`.

Solution

``class Solution {    public int uniquePaths(int m, int n) {        int[] temp = new int[m];        for (int i = 0; i < m; i++)            temp[i] = 1;        for (int j = 0; j < n-1; j++){            for (int c = 1; c < m; c++){                temp = temp[c-1] + temp;            }        }        return temp[m-1];    }}``

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