Go: package main

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

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		M, T, P, R := io.NextInt(), io.NextInt(), io.NextInt(), io.NextInt()
		if M == 0 {
			break
		}
		score := make([]struct{ num, time, index int }, T)
		submit := make([][]int, T)
		for i := 0; i < T; i++ {
			score[i].index = i + 1
			submit[i] = make([]int, P)
		}

		for i := 0; i < R; i++ {
			m, t, p, j := io.NextInt(), io.NextInt()-1, io.NextInt()-1, io.NextInt()
			if j == 0 {
				score[t].num++
				score[t].time += submit[t][p]*20 + m
			} else {
				submit[t][p]++
			}
		}
		sort.SliceStable(score, func(i, j int) bool {
			return score[i].num < score[j].num || score[i].num == score[j].num && score[i].time > score[j].time
		})

		for i := T - 1; i > 0; i-- {
			io.Printf("%d", score[i].index)
			if score[i].num == score[i-1].num && score[i].time == score[i-1].time {
				io.Printf("=")
			} else {
				io.Printf(",")
			}
		}
		io.Println(score[0].index)
	}
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

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

const int INF=50000000;

int data[51][12];

int main(){
	int M,T,P,R;
	while(cin>>M>>T>>P>>R && M){
		fill((int*)data,(int*)(data+12),0);
		for(int i=0;i<R;i++){
			int m,t,p,j;
			cin>>m>>t>>p>>j;
			if(j==0){
				data[t][0]++;
				data[t][11]+=m+data[t][p]*20;
			}
			else data[t][p]++;
		}
		int prev[2]={INF,0};
		for(int i=0;i<T;i++){
			int ans=0;
			int now[2]={0,INF};
			for(int j=T;j>=0;j--){
				if(data[j][0]>now[0]){
					now[0]=data[j][0];
					now[1]=data[j][11];
					ans=j;
				}
				else if(data[j][0]==now[0] && data[j][11]<now[1]){
					now[1]=data[j][11];
					ans=j;
				}
			}
			if(i){
				if(memcmp(now,prev,sizeof(now))==0)cout<<"=";
				else cout<<",";
			}
			cout<<ans;
			memcpy(prev,now,sizeof(now));
			data[ans][0]=-1;
		}
		cout<<endl;
	}
	cout<<endl;
}

C++: #include<iostream>
#include<vector>
#include<map>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<string>
#include<algorithm>
#define INF 1e9
#define M_Team 50
#define M_Pro 10

typedef long long int ll;
using namespace std;

int wacount[M_Team+1][M_Pro+1]={};
int timesum[M_Team+1]={},anssum[M_Team+1];
vector<char> ans;


void set(int n){
	if(n <10)
		ans.push_back(n+'0');
	else{
		ans.push_back(n/10+'0');
		ans.push_back(n%10+'0');
	}
}

void out(int timesum[M_Team+1],int grad[M_Team+1],int T){
	set(grad[0]+1);
	for(int i=1;i<T;i++){
		if(anssum[ grad[i] ]==anssum[ grad[i-1] ]  &&  timesum[ grad[i] ] == timesum[ grad[i-1] ] ){
			ans.push_back('=');
			set(grad[i]+1);
		}else{
			ans.push_back(',');
			set(grad[i]+1);
		}
	}
	for(int i=0;i<ans.size();i++)cout<<ans[i];
	cout<<endl;
}

bool checkOver(int a,int b){
	if(anssum[a] <  anssum[b])return true;
	if( (anssum[a] == anssum[b]) && (timesum[a]>timesum[b]) )return true;
	return false;
}


void babu_sort(int anssum[M_Team+1],int timesum[M_Team+1],int grad[M_Team+1],int T){
	for(int i=0;i<T;i++)
		for(int j=0;j<T-i-1;j++)
			if( checkOver(grad[j],grad[j+1]) )
				swap(grad[j],grad[j+1]);
}

void solve(int anssum[M_Team+1],int timesum[M_Team+1],int M,int T,int P,int R){
	int grad[M_Team+1];
	for(int i=0;i<T;i++)
		grad[i]=T-i-1;
//for(int i=0;i<T;i++)cout<<grad[i];cout<<endl;
	babu_sort(anssum,timesum,grad,T);
//for(int i=0;i<T;i++)cout<<grad[i];cout<<endl;
	out(timesum,grad,T);
}

int main(){
	while(1){
//初期化
		ans.clear();
		for(int i=0;i<M_Pro+1;i++){
			for(int j=0;j<M_Team+1;j++){
				wacount[i][j]=0;
			}
			timesum[i]=0;
			anssum[i]=0;
		}
///////
		int M,T,P,R;
		int m,t,p,J;
		cin>>M>>T>>P>>R;
		if(M==0 && T==0 && P==0 && R==0)break;
		for(int i=0;i<R;i++){
			cin>>m>>t>>p>>J;
			t--;
			if(J!=0){
				wacount[t][p]++;
			}
			else{
				timesum[t]+=m+wacount[t][p]*20;
				anssum[t]++;
			}
		}
		solve(anssum,timesum,M,T,P,R);
	}
	return 0;
}

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

using namespace std;

typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> VI;
typedef vector<VI> VVI;
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
const int INF = numeric_limits<int>::max() / 2;
const int NEG_INF = numeric_limits<int>::min() / 2;

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  int m,t,p,r;
  while(true){
    cin >>m >> t >> p >> r;//???????????°???????????°?????¬???????????°
    if(t==0) break;
    int seikai[t+1]={0},penalty[t+1]={0},gotou[t+1][p+1]={0};
    for(int i=0;i<r;i++){
      int j,tID,pID,time;
      cin >> time>> tID >> pID >> j;
      if(j==0){
        seikai[tID]++;
        penalty[tID] += gotou[tID][pID]*20+time;
      }
      else{
        gotou[tID][pID]++;
      }
    }
    bool checked[t+1]={false};
    int preseikai=-1,prepena=-1;
    for(int i=t;i>=1;i--){
      int team,seikaimax=-1,pena=INF;
      for(int j=t;j>=1;j--){
        if(!checked[j]){
          if(seikaimax<seikai[j]){
            seikaimax=seikai[j];
            team=j;
            pena=penalty[j];
          }
          else if(seikaimax==seikai[j]){
            if(pena>penalty[j]){
              team=j;
              pena=penalty[j];
            }
          }
        }
      }
      checked[team]=true;
      if(prepena==-1) cout << team ;
      else if(prepena==pena && preseikai==seikaimax) cout << "=" << team;
      else cout << "," << team;
      preseikai=seikaimax,prepena=pena;
    }
    cout << endl;
  }
}