题解 | #走方格的方案数#没啥好解释上菜

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int n, m;
    cin >> n >> m;

    vector<vector<int>> dp(n + 1, vector<int>(m + 1, 0));

    for (int i = 0; i < dp[0].size(); ++i) dp[0][i] = 1;
    for (int i = 0; i < dp.size(); ++i) dp[i][0] = 1;

    for (int i = 1; i < dp.size(); ++i) {
        for (int j = 1; j < dp[0].size(); ++j) {
            dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
        }
    }

    cout << dp[n][m] << endl;
    return 0;
}
// 64 位输出请用 printf("%lld")