LeetCode: Unique Paths

一次过

class Solution {
public:
    int uniquePaths(int m, int n) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<vector<int>> f(m+1, vector<int>(n+1, 0));
        if (m <= 1 || n <= 1) return 1;
        for (int i = 1; i <= m; i++) f[i][1] = 1;
        for (int i = 1; i <= n; i++) f[1][i] = 1;
        for (int i = 2; i <= m; i++) {
            for (int j = 2; j <= n; j++) {
                f[i][j] = f[i][j-1] + f[i-1][j];
            }
        }
        return f[m][n];
    }
};

 C#

public class Solution {
    public int UniquePaths(int m, int n) {
        int[,] f = new int[m+1, n+1];
        if (m <= 1 || n <= 1) return 1;
        for (int i = 1; i <= m; i++) f[i, 1] = 1;
        for (int i = 1; i <= n; i++) f[1, i] = 1;
        for (int i = 2; i <= m; i++) {
            for (int j = 2; j <= n; j++) {
                f[i, j] = f[i, j-1] + f[i-1, j];
            }
        }
        return f[m, n];
    }
}