Unique Paths in a Grid?

int UniquePaths(int m, int n) {
int[,] dp = new int[m, n];
for (int i = 0; i < m; i++) dp[i, 0] = 1;
for (int j = 0; j < n; j++) dp[0, j] = 1;
for (int i = 1; i < m; i++) {
for (int j = 1; j < n; j++) {
dp[i, j] = dp[i - 1, j] + dp[i, j - 1];
}
}
return dp[m - 1, n - 1];
}

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