class Solution {
  public:
    /**
     *
     * @param m int整型
     * @param n int整型
     * @return int整型
     */
    int uniquePaths(int m, int n) {
        // dp[i][j] = dp[i-1][j]+ dp[i][j-1]
        vector<vector<int> > dp(m + 1, vector<int>(n + 1, 1));
        for (int i = 2; i < m + 1; i++) {
            for (int j = 2; j < n + 1; j++) {
                dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
            }
        }
        return dp[m][n];
    }
};