20150204
http://codeforces.com/problemset/problem/509/A
代码:
#include <iostream>
using namespace std;
int s[12];
int d[12];
int main()
{
int n;
cin >> n;
for(int i = 0; i < n; i++)
s[i] = 1;
for(int i = 1; i < n; i++){
for(int j = 0; j < n; j++){
if(j == 0)
d[j] = s[j] + 1;
else
d[j] = d[j-1] + s[j];
}
for(int j = 0; j < n; j++)
s[j] = d[j];
}
if(n >= 2)
cout << d[n-2] << endl;
else
cout << 1 << endl;
return 0;
}