1799.cpp

杭电 acm部分代码 有兴趣的可以下载 谢谢

#include <iostream>
using namespace std;

int c[2002][2002] = {0};

int main()
{
    int i, j, test;
    for (i = 1; i <= 2000; i++)
    {
        c[i][0] = 1;    
        c[i][1] = i % 1007;
    }
    for (i = 2; i <= 2000; i++)
    {
        for (j = 2; j <= i; j++)
        {
            c[i][j] = (c[i - 1][j] % 1007 + c[i - 1][j - 1] % 1007) % 1007;
        }
    }
    cin >> test;
    while (test--)
    {
        cin >> i >> j;
        if (j >= i)
        {
            if (i == 0)
            {
                cout << "0" << endl;
            }
            else
            {
                cout << c[j][i] << endl;
            }
        }
        else
        {
            cout << "0" << endl;
        }
    }
    return 0;
}