///////////// pascle NCR

///////////// pascle NCR
#include<bits/stdc++.h>
using namespace std;
#define scInt(x,y) scanf("%d%d",&x,&y)
int dp[1000][1000];
int start;
int NCR(int n,int r)
{
    if(dp[n][r])
        return dp[n][r];
    int i,j;
    for(i=start; i<=n; i++)
    {


        for(j=0; j<=n; j++)
        {

            if(i==j){

                dp[i][j]=1;

            break;
            }
            if(j==0){

                dp[i][j]=1;

            continue;
            }
            dp[i][j]=dp[i-1][j]+dp[i-1][j-1];


        }
        if(dp[n][r])
        {
            start=i;
            return dp[n][r];
        }
    }
}



int main()
{
    start=0;
int n,r;
    while(scInt(n,r)!=EOF)
    {


        printf("NCR of %dc%d: %d\n",n,r,NCR(n,r));


    }



}