201301 JAVA题目2-3级

这道题目和 leetcode62 路径数量一样的，唯一不同的就是牛客网n,m需要加1，这样才能够运行。

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;

int uniquePaths(int m, int n) 
{
    if (m < 1 || n < 1) return 0;
    vector<vector<int>> d(m,vector<int>(n,0));

    for (int j = 0; j < n; j++)
        d[0][j] = 1;
    for (int i = 0; i < m; i++)
        d[i][0] = 1;

    for (int i = 1; i < m; i++)
        for (int j = 1; j < n; j++)
            d[i][j] = d[i - 1][j] + d[i][j-1];

    return d[m-1][n-1];
}

int main()
{
    int n = 0;
    int m = 0;

    while (cin >> n >> m)
    {
        cout << uniquePaths(n+1,m+1) << endl;
    }

    return 0;
}