Go: package main

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

var (
	sc = bufio.NewScanner(os.Stdin)
)

func main() {
	for sc.Scan() {
		if sc.Text() == "0 0" {
			break
		}
		chunks := strings.Split(sc.Text(), " ")
		n, _ := strconv.Atoi(chunks[0])
		p, _ := strconv.Atoi(chunks[1])
		cnts := make([]int, n, n)
		for i := 0; true; i++ {
			j := i % n
			if p == 0 {
				p, cnts[j] = cnts[j], 0
			} else {
				cnts[j]++
				p--
			}

			if p == 0 {
				noneCnt := 0
				winner := 0
				for j, c := range cnts {
					if c == 0 {
						noneCnt++
					} else {
						winner = j
					}
				}
				if noneCnt == n-1 {
					fmt.Println(winner)
					break
				}
			}
		}
	}
}

C++: #include <bits/stdc++.h>
using namespace std;

template<class T>
bool chmax(T& a, const T& b) {
    if (a < b) { a = b; return true; }
    return false;
}
template<class T>
bool chmin(T& a, const T& b) {
    if (b < a) { a = b; return true; }
    return false;
}

// std::vector Declaration
template<typename T>
vector<T> make_v(size_t a) { return vector<T>(a); }
template<typename T, typename... Ts>
auto make_v(size_t a, Ts... ts) {
    return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}

// std::vector Declaration and Initialization
template<typename T>
vector<T> make_vector(size_t a, T x) { return vector<T>(a, x); }
template<typename T, typename U, typename... Ts>
auto make_vector(size_t a, U b, Ts... ts) {
    return vector<decltype(make_vector<T>(b,ts...))>(a, make_vector<T>(b, ts...));
}

// std::vector Input
template<typename T>
istream& operator>>(istream& is, vector<T>& v) {
    for (auto &e : v) is >> e;
    return is;
}

// std::vector Debug
template<typename T>
ostream& operator<<(ostream& os, const vector<T>& v) {
    os << "[";
    bool a = 1;
    for (auto e : v) {
        os << (a ? "" : " ");
        os << e;
        a = 0;
    }
    os << "]";
    return os;
}

// std::array Debug
template<typename T, size_t n>
ostream& operator<<(ostream& os, const array<T, n>& v) {
    os << "[";
    bool a = 1;
    for (auto e : v) {
        os << (a ? "" : " ");
        os << e;
        a = 0;
    }
    os << "]";
    return os;
}

// std::deque Debug
template<typename T>
ostream& operator<<(ostream& os, const deque<T>& d) {
    os << "[";
    bool a = 1;
    for (auto e : d) {
        os << (a ? "" : " ");
        os << e;
        a = 0;
    }
    os << "]";
    return os;
}

// std::pair Debug
template<typename T, typename U>
ostream& operator<<(ostream& os, const pair<T, U>& p) {
    os << "(" << p.first << " " << p.second << ")";
    return os;
}

// std::set Debug
template<typename T>
ostream& operator<<(ostream& os, const set<T>& st) {
    os << "{";
    bool a = 1;
    for (auto e : st) {
        os << (a ? "" : " ");
        os << e;
        a = 0;
    }
    os << "}";
    return os;
}

// std::multiset Debug
template<typename T>
ostream& operator<<(ostream& os, const multiset<T>& st) {
    os << "{";
    bool a = 1;
    for (auto e : st) {
        os << (a ? "" : " ");
        os << e;
        a = 0;
    }
    os << "}";
    return os;
}

// std::map Debug
template<typename T, typename U>
ostream& operator<<(ostream& os, const map<T, U>& mp) {
    os << "{";
    bool a = 1;
    for (auto e : mp) {
        os << (a ? "" : " ");
        os << e.first << ":" << e.second;
        a = 0;
    }
    os << "}";
    return os;
}

// std::tuple Debug
template<int N, class Tuple>
void out(ostream& os, const Tuple& t){}
template<int N, class Tuple, class H, class ...Ts>
void out(ostream& os, const Tuple& t) {
    if (N) os << " ";
    os << get<N>(t);
    out<N+1,Tuple,Ts...>(os, t);
}
template<class ...Ts>
ostream& operator<<(ostream& os, const tuple<Ts...>& t) {
    os << "(";
    out<0,tuple<Ts...>,Ts...>(os, t);
    os << ")";
    return os;
}

// Debug
#define DUMP(x) cerr<<#x<<" = "<<(x)<<endl

// Weighted edge
template<typename T>
struct edge {
    int src, to;
    T cost;

    edge() {}
    edge(int to, T cost) : src(-1), to(to), cost(cost) {}
    edge(int src, int to, T cost) : src(src), to(to), cost(cost) {}

    friend ostream& operator<<(ostream& os, const edge& e) {
        return os << "(" << e.src << "->" << e.to << ":" << e.cost << ")";
    }
};

using LL = long long;

#define fs first
#define sc second

const LL MOD = 1e9+7;


int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);

    while (true) {
        int n, p; cin >> n >> p;
        if (n == 0 && p == 0) {
            break;
        }

        vector<int> s(n);
        int b = p;
        int ans = -1;

        for (int i = 0; ; i = (i+1)%n) {
            if (b == 0) {
                b += s[i];
                s[i] = 0;
            } else {
                --b;
                if (++s[i] == p) {
                    ans = i;
                    break;
                }
            }
        }

        cout << ans << endl;
    }

    return 0;
}

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


using namespace std;

int main(){
	int n,r;
	while(cin >> n >> r,n){
		int p[n];
		fill(p,p+n,0);
		int s = r;
		for(int i = 0;;i++,i %= n){
			if(p[i] == r){
				cout << i << endl;
				break;
			} else {
				if(s == 0){
					s += p[i];
					p[i] = 0;
				} else {
					p[i]++;
					s--;
				}
			}
		}
	}
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#include<cstdio>
#include<cmath>
using namespace std;

#define ll long long int
#define ld long long double
#define reps(i,f,n) for(int i=f;i<n;i++)
#define rep(i,n) reps(i,0,n)
#define m1 cout<<"move1"<<endl
#define m2 cout<<"move2"<<endl
#define m3 cout<<"move3"<<endl
#define m4 cout<<"move4"<<endl


int main(){
  vector<int> v(100);
  ll N;
  ll S;
  ll ans= -1;
  ll win = 0;
  while(cin>>N,cin>>S, N != 0 && S != 0){
    ans = S;
    rep(i,100) v.push_back(0);
    while(1){
      for(int i=0;i<N;i++){
	if(S == 0){
	  S = v[i];
	  v[i] = 0;
	}
	else{
	  v[i]++;
	  S--;
	  //m1;
	}
	if( v[i] == ans){
	  win = i;
	  break;
	}
      }
      if(ans != -1){
	cout<<win<<endl;
	ans = -1;
	break;
      }
    }
      
  }
	  
  return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
int main() {
	int n, p;
	while (cin >> n >> p && n) {
		vector<int> line(n, 0);
		int hn = 0;
		for (int i = 0; i < n; ++i) {
			line[i] = p / n + (p%n > i ? 1 : 0);
			if (line[i])++hn;
		}
		int place = p % n;
		p = 0;
		while (true) {
			if (p == 0) {
				if (line[place])--hn;
				p = line[place];
				line[place] = 0;
			}
			else {
				if (line[place] == 0)++hn;
				++line[place];
				--p;
			}
			if (p == 0 && hn == 1) {
				cout << place << endl;
				break;
			}
			place = (place + 1) % n;
		}
	}
	return 0;
}

C++: #include<iostream>
using namespace std;

int main(){
	int people;
	int stone;
	int hand[50];

	while(1){
		for(int j=0; j < 50; j++) hand[j] = 0;

		int ans;
		cin >> people >> stone;
		if((people|stone) == 0) break;

		int box = stone;
		int i=0;
		while(1){
			if(box > 0){
				hand[i]++;
				box--;
			}
			else{
				box += hand[i];
				hand[i] = 0;
			}
			if(hand[i] == stone){
				ans = i;
				break;
			}
			i = (i + 1)%people;
		}
		cout << ans << endl;
	}
	return 0;
}