Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"fmt"
)

func solve(a, b, c int) int {
	if a == 1 && b >= c && b < 10 {
		return 1
	}
	if a == 1 {
		return 0
	}
	ret := 0
	for i := c; i < 10 && i < b; i++ {
		ret += solve(a-1, b-i, i+1)
	}
	return ret
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	for {
		scanner.Scan()
		a, _ := strconv.Atoi(scanner.Text())
		if a == 0 {
			break
		}
		scanner.Scan()
		b, _ := strconv.Atoi(scanner.Text())
		fmt.Println(solve(a, b, 0))
	}
}

C++: #include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < int(n); i++)
#define rrep(i, n) for (int i = int(n) - 1; i >= 0; i--)
#define reps(i, n) for (int i = 1; i <= int(n); i++)
#define rreps(i, n) for (int i = int(n); i >= 1; i--)
#define repc(i, n) for (int i = 0; i <= int(n); i++)
#define rrepc(i, n) for (int i = int(n); i >= 0; i--)
#define repi(i, a, b) for (int i = int(a); i < int(b); i++)
#define repic(i, a, b) for (int i = int(a); i <= int(b); i++)
#define repp(i, n) rep(i, n)
#define reppp(i, n) repp(i, n)
#define rrepp(i, n) rrep(i, n)
#define repss(i, n) reps(i, n)
#define repcc(i, n) repc(i, n)
#define repii(i, a, b) repi(i, a, b)
#define each(x, y) for (auto &x : y)
#define all(a) (a).begin(), (a).end()
#define bit(b) (1ll << (b))

using namespace std;

using i32 = int;
using i64 = long long;
using u64 = unsigned long long;
using f80 = long double;
using vi32 = vector<i32>;
using vi64 = vector<i64>;
using vu64 = vector<u64>;
using vf80 = vector<f80>;
using vstr = vector<string>;

inline void yes() { cout << "Yes" << '\n'; exit(0); }
inline void no() { cout << "No" << '\n'; exit(0); }
inline i64 gcd(i64 a, i64 b) { if (min(a, b) == 0) return max(a, b); if (a % b == 0) return b; return gcd(b, a % b); }
inline i64 lcm(i64 a, i64 b) { return a / gcd(a, b) * b; }
inline u64 xorshift() { static u64 x = 88172645463325252ull; x = x ^ (x << 7); return x = x ^ (x >> 9); }
void solve(); int main() { ios::sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(16); solve(); return 0; }
template <typename T> class pqasc : public priority_queue<T, vector<T>, greater<T>> {};
template <typename T> class pqdesc : public priority_queue<T, vector<T>, less<T>> {};
template <typename T> inline void amax(T &x, T y) { if (x < y) x = y; }
template <typename T> inline void amin(T &x, T y) { if (x > y) x = y; }
template <typename T> inline T power(T x, i64 n, T e = 1) { T r = e; while (n > 0) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; }
template <typename T> istream& operator>>(istream &is, vector<T> &v) { each(x, v) is >> x; return is; }
template <typename T> ostream& operator<<(ostream &os, vector<T> &v) { rep(i, v.size()) { if (i) os << ' '; os << v[i]; } return os; }
template <typename T, typename S> istream& operator>>(istream &is, pair<T, S> &p) { is >> p.first >> p.second; return is; }
template <typename T, typename S> ostream& operator<<(ostream &os, pair<T, S> &p) { os << p.first << ' ' << p.second; return os; }

void solve() {
  int n, s;
  int ans;
  vi32 v(10);
  function<void(int, int)> rec = [&](int x, int i) {
    if (x == n) {
      int sum = accumulate(all(v), 0);
      if (sum == s) ans++;
      return;
    }
    repic(j, i + 1, 9) {
      v.push_back(j);
      rec(x + 1, j);
      v.pop_back();
    }
  };

  while (true) {
    cin >> n >> s;
    if (n == 0) return;
    ans = 0;
    rec(0, -1);
    cout << ans << '\n';
  }
}

C++:  
 #include<iostream>
 #include<stdio.h>
 #include<string>
 #include<math.h>
 #include<iomanip>
 #include<algorithm>
 #include<string.h>
 #include<cctype>
 #include<map>
 #include<set>
 #include<vector>
 #include<sstream>
 #include<stack>
 #include<queue>
 
 using namespace std;
 
 int a[10]={0,1,2,3,4,5,6,7,8,9};
 int n,s;
 int count_2;
 
 void dfs(int step,int i,int sum)
 {
   if(sum>s||step>n) return;
   if(step==n&&i==10&&sum==s)
   {
     count_2++;
     return;                          
   }     
   dfs(step,i+1,sum); 
   dfs(step+1,i+1,sum+a[i]);
   return;
 }
  
 int main()
 {
   while(cin>>n>>s)
   {
     if(n==0&&s==0) break;
     else
     {
       count_2=0;
       dfs(0,0,0);    
     } 
     cout<<count_2<<endl;               
   }
   //while(1);     
   return 0;  
 }

C++: #include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <utility>
#include <stack>
#include <functional>
#include <queue>
#include <cmath>

#define rep(i,j,k) for(int i=j;i<k;i++)
#define drep(n,m) for(int i=0;i<n;i++)for(int j=0;j<m;j++)
#define fi first
#define se second
#define vi vector<int>
#define INF 1000000000
#define MOD 1000000009
#define pb push_back
#define mp make_pair
typedef long long ll;
int dx[4]={0,1,0,-1},dy[4]={1,0,-1,0};

using namespace std;

ll gcd(ll a,ll b){
    if(a<b){
        int t=a;a=b;b=t;
    }
    int c=a%b;
    while(c!=0){
        a=b;
        b=c;
        c=a%b;
    }
    return b;
}

ll lcm(ll a,ll b){
    return a*b/gcd(a,b);
}

bool isPrime(int x){
    if(x==1)return false;
    if(x==2)return true;
    if(x%2==0)return false;
    for(int i=3;i<=sqrt(x);i+=2){
        if(x%i==0)return false;
    }
    return true;
}

int kaizyo(int x){
    if(x==1)return x;
    else return x*kaizyo(x-1);
}

vector<int> v(10);
int n,s;
int ans=0;
void dfs(int sum,int ct,int i){
    if(ct==n){
        if(sum==s)ans++;
        return;
    }
    if(i==10)return;
    
    dfs(sum+v[i],ct+1,i+1);
    dfs(sum,ct,i+1);
    return;
}
int main() {
    rep(i,0,10)v[i]=i;
    while(1){
        ans=0;
        cin>>n>>s;
        if(n==0&&s==0)break;
        dfs(0,0,0);
        cout<<ans<<endl;
    }
  
    return 0;
}

C++: #include <iostream>
#include <bitset>

using namespace std;

int main() {
    int a[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
    int n, s, sum, cnt;

    while (cin >> n >> s) {
        if (!n && !s) { break; }
        cnt = 0;
        for (int i = 0; i < (1 << 10); i++) {
            sum = 0;
            for (int j = 0; j < 10; j++) {
                // if (bitset<10>(i).test(j)) {
                if (i & (1 << j)) {
                    sum += a[j];
                }
            }
            if (sum == s && bitset<10>(i).count() == n) { cnt++; }
        }
        cout << cnt << endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i,l,n) for(int i=l;i<n;i++)
#define rer(i,l,n) for(int i=l;i<=n;i++)
#define all(a) a.begin(),a.end()
#define o(a) cout<<a<<endl
#define pb(a) push_back(a)
#define mk(a,b) make_pair(a,b)
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;

int ans,n,s;

void dfs(int i,int sum,int m){
	if(i==0){
		if(sum==s){
			ans++; //o(m);
		}
		return;
	}
	rep(j,m,10){
		dfs(i-1,sum+j,j+1);
	}
}

int main(){
	while(1){
		cin>>n>>s;
		if(n==0 && s==0) break;
		ans=0;
		dfs(n,0,0);
		o(ans);
	}
}

C++: import java.util.Scanner;
public class Main {
	public static final int limit = 9;
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		while(true){
			int n=s.nextInt();
			int m=s.nextInt();
			if(n==0&&m==0)break;
			System.out.println(s(n,m,0));
		}

	}
	public static int s(int n,int m,int x){
		if(n==1){
			return x<=m&&m<=limit?1:0;
		}
		int a=0;
		for(int i=x;i<=limit;i++){
			a+=s(n-1,m-i,i+1);
		}
		return a;
	}
}